Dead Space 3 is a good sequel to the second game. Before we begin, I should disclaim that I never was upset at the apparent shift to action the sequel; to me DS was always an action game with gnarly enemy designs, rather than a horror game. So the shift to including human enemies and more firepower was not a problem for me.
Despite not finding the game to be true horror, there were segments from the previous games I did find unsettling; 3 has less of the stuff than the prior games that I found disconcerting (Isaac's sanity slippage and the preschool from the second game), but it doesn't detract too much from the actual end product. Plus, the first encounter with the Feeders was tense enough. Otherwise, the previous game depended on jumpscares, which DS3 does provide; the fact that Necromorphs can burst out of the snow, rather than out of identical looking vents, actually makes predicting their spawns somewhat harder once you reach Tau Volanits.
Gameplay wise, it feels quite similar to 2, which is a good thing. Combat is exciting and fun. The new gunsmithing mechanic was rather addictive for me; I loved seeing what combinations you could get and testing them out. While I kept the plasma cutter as my mainstay, experimenting with various backups was fun. The new universal ammo system might detract from the horror for some, though not me. There did seem to be fewer zero-G sequences, which I did miss.
Resource collection and microtransactions are contentious. I can see how that would irk many people, but I found enough materials to fully upgrade both guns and my rig before the end of the game without paying. Additionally, you can find ingame items that will allow you to buy microtransactions in lieu of real cash.
One downside is the plot. The overarching plot is fine; it didn't feel out of place. However I would've found it helpful if we were given more backstory, both on the collapse of EarthGov and on what the Sovereign Colonies were. However, an unnecessary portion of the game is taken up by a poorly-done love triangle, which hurts the overall plot and derails the character at the point.
I have yet to play co-op or the new gameplay modes opened up after completion, so I cannot weigh in on them. All-in-all I'd recommend this to fans of the early games, as long as they can put up with some more gunplay.