Mass Effect 2 is an excellent follow up to Mass Effect, in almost every possible way.
The shooting mechanics have been completely overhauled, the villains are more interesting, the graphics are better, the biotic powers and the UI are more entertaining and easier to use, heck even the Normandy is cooler than before.
That’s also the only problem with Mass Effect 2. BioWare retooled this game into much more of a third person shooter with RPG elements than the original, which was an RPG with third person shooter elements. You can no longer freely explore planet surfaces, but are forced into the invisible walled areas they’ve designed for the game. You also no longer control the equipment your party uses or their skills to as great of an extent as the first game.
Combat is much easier this time around. Where shooting previously felt like an obstacle you begrudgingly had to knock out of the way in order to progress in the original game, in the sequel it feels much more like BioWare wanted you to enjoy the combat. In fact the combat feels so good, that it honestly feels like it was the focus of the game design. The FOV and camera angles are closer to Shephard so you can see the work they put into the animations. You can manually reload your gun now instead of having infinite energy, and you see the spent plasma cartridges as they eject from the weapon, hissing on the way down. The shooting effects and abilities like overcharge, or consumables like the ammo, feel meatier and enemies don’t just run at you until they die, which was often the case with husks in the first game with every weapon but the shotgun.
Fortunately those limited areas have been crafted to produce some great experiences, like when you first get Jack.
The paragon/rogue system is also pretty much meaningless in this game. You have to intentionally be a jerk at every possible opportunity in order to not get paragon. If you don’t commit to it, there’s no feasible way you could beat the game without being a nice guy.
Even so, the game is still good fun with a great story and great voice acting, with characters you can care about. If you aren’t already using it, please get the ALOT mod as it makes this an entirely different experience than playing it on console (even though it is just textures).