I first played this mod in 2019. It adds a few little tweaks to bring the game closer to the Classics, but more importantly it adds hands with animations to several weapon models and the gibbing system from SS3, which is much superior to the original system. Still, none of the changes are radical enough to make it feel like a different game.

Recently Renovation Mod has been integrated into the Steam version (though you still have to select it from the menu), which tells me that the devs approve of it and don't see it as contradicting their vision. In addition, the Steam version has received a few massive updates throughout the years, most notably the 2021 update which added optional sprinting, radar and dual-wielding. The latter in particular is a massive change because it wrecks the balance. You can dual wield any weapon, even the canon, thus doubling either your fire-rate or firepower, something the game was not designed around. For weapons that were already dual-wielded (pistols, UZIs), enabling dual-wielding allows you to control each hand individually with their respective mouse buttons.

The reason so many changes have been made to SS2 is probably because Croteam has been somewhat unhappy about how it turned out. It seems after the first game and its expansion dropped, they had a temporary lapse in judgement during which they decided the series should go in a more cartoony and insane direction. First the Xbox port of the Classics got new models, cutscenes with more story (with more emphasis on jokes), and the practical HUD of the PC version was replaced with something less-cluttered and more visual, but ultimately less informative. Then the outsourced Next Encounter came out, which pushed even further in that direction with more exaggerated enemy designs and even more humorous dialogues and gags in the cutscenes. SS2 was kinda the culmination of all that, but this time it was a mainline sequel, so the fan reaction was polarized.

By the time SS3 got released, Croteam had backpedaled hard, arguably even too hard. The first game and its expansion were colorful, tongue-n-cheek and had humorous moments that coexisted with a mysterious atmosphere, and immersive and relatively-realistic environments and enemy designs. SS3 and subsequently SS4 are noticeably less colorful and less cartoony, but I'd argue they're much closer in spirit to the Classics. In addition to Croteam's 180 on the course of the series' identity, they officially declared SS2 to be non-canon, alongside Next Encounter. It's also known that they once planned to remaster it, and the leaks seem to suggest that the remaster would've been more of a remake closer in style to the rest of the mainline series.

I don't particularly care for the canon of Serious Sam because I don't particularly care for its story. I think until SS4 the story in Serious Sam games was purely practical and didn't present anything special. However, I think the decanonization is just because SS2 doesn't feel like a Serious Sam game to me, almost at all.

It seems to be more of a sequel to Next Encounter than the first game, and I mean that both mechanically and stylistically. While it's definitely not as much of an offender as NE, it's plagued with a lot of the same problems. The levels are very linear compared to the rest of the series, invisible walls galore. Most combat scenarios consist of simplistic arenas with waves of respawning enemies, a-la the last level of TFE before the final boss. Most enemies here are new and most of them have pretty basic attack patterns and behaviors. Melee enemies usually just charge you, ranged enemies usually shoot you with whatever random projectiles in a straight line. Doesn't matter whether it's rockets, bullets or lasers. The kamikazes blow up even from a single bullet, just like in NE, the Kleers and Werebulls (who are now toy rhinos for whatever reason) have none of the weight and physics that made dodging them an elegant waltz in the original. Whatever classic enemies did make it here, have local equivalents as well for whatever reason. There are now several annoying flying enemies that are hard to hit, while the original had only Gnaars and Harpies, both of which had predictive movement patterns that made shooting them easy and fun. The weapon placement now makes no sense either. They give you a plasma rifle before introducing the flying witches, but why would you use a projectile-based weapon against a highly mobile flying enemy? You don't yet even have the UZIs in that level, so relying on your shotgun is the best option, but the game effectively guides you to use the plasma rifle. In fact the game kinda suffers from the same problem NE suffered from, which is making most weapons equally effective against most enemies. The rocket launcher is in fact weaker than the double-barreled shotgun, which makes it almost useless, especially after you discover the sniper rifle.

Also there's now turret sections and vehicles that are just boring as hell. Vehicles first made their debut in Next Encounter and then reappeared in SS4, except in SS4 they're mostly just transport or (in the case of mechs) have more of a nuanced gameplay. Here you have entire minutes-long battles on vehicles, which boil down to holding down the fire button. In fact, most battles feel that way. I did find myself switching between weapons more than in Next Encounter, but much less so than in the Classics, SS3 or SS4. Simply because most enemies behave the same, which kinda also removes the need to think strategically about which enemies should be prioritized.

But really, put simply, the problem here is that it just doesn't have the trademark Serious Sam gameplay. Take for example the Valley of the Jaguar from TSE. It's a giant map that you enter through a cave, the entrance of which has two mountains on its sides. There's a pyramid in the middle flat plane and three other pyramids on surrounding mountains. As soon as you enter the location, a horde starts coming at you, forced into the narrow passage between the mountains, which gives you an advantage. If you play your cards right, you can take out most dangerous enemies before the horde reaches you, and there's enough space to dodge their attacks. Once you do that and proceed to the middle plane, from there you have a number of approaches to the consequent battles, as you can take higher ground in one of the mountain pyramids, explore two other narrow passages which may hold secrets, or make your stand at the central pyramid, giving you a good observation of the entire location, allowing you to spot the enemies as soon as they spawn in every corner of the map. There's not a single map in SS2 that's even remotely similar. Forget about exploration and strategizing. It's just arenas and corridors with respawning enemies. Some locations are big, but they're essentially simple flat squares with some houses thrown around for some basic cover. The game ultimately plays as a pretty basic shooter a-la Painkiller.

But even if you forget about gameplay, there is only a tangential similarity with the previous or subsequent installments of its franchise. Mostly just a relatively-similar tone. RELATIVELY. It is much more cartoony, making it harder to take anything seriously, but yes, the first game was somewhat cartoony and humorous while also being bloody and adult-oriented. The essence hasn't changed, only the degree.

What did change is that the sense of place that I praised SS1, 3 and 4 is completely gone here. Like TSE and 4, SS2 is composed of several major locations, each of which resets your inventory. However the locations here are made-up planets that resemble caricatures of certain real-life cultures. They do look gorgeous and would probably be fascinating places to explore, but there's hardly any exploration here because of just how linear the levels are. In addition, NETRICSA, which was a database of text in the first game, which gave you optional context that made the past of these locations come to life, here became a sentient blue woman, a parody of Cortana from Halo for whatever reason.

In the end, I have to say that other than some really nice visuals, there's very little I enjoyed about this game. It certainly doesn't feel like a Serious Sam game, but it also doesn't really stand on its own due to its mechanical simplicity. The updates may have altered the core gameplay a little, but the content is still the same and is still just as basic.