It's not enough to say I finished Mass Effect 3. Someone who has a character imported through the prior games has the powerful experience of having completed an epic trilogy with a customized story line altered by your decisions from prior games. It's the first time I've played a series of games like this, and it certainly enhances the experience, the anticipation, and to a small degree, a level of customization based on personal preferences. I'm probably going to talk about some spoilers ahead, so you know...
There are a lot of great things about a game series like this, as well a lot of terrible things. By the time the third game in a series like this comes out, everyone's anticipation level is pretty high and their expectations are pent up like charged springs, and they're ready to launch their customized Shepards into a new set of challenges and wrap up an epic trilogy. This sort of pent-up anticipation is also a breeding ground for disappointment. It's a monumental hurdle for game creators to deal with these sorts of expectations. Not only are they living up to old games, they're living up to the integrity of their particular story against the millions of nuanced opinions and wishes of their customers.
Combat in ME3 is much more challenging than the prior games. I've played through all them on "normal" difficulty settings and I could fairly confidently walk through every battle in the first two games. The third game took me off guard and I had to really assess what I was doing in order to survive. It's a good kind of challenging. Not impossible, but you had to earn your victory in some areas. Surprisingly, fighting Cerberus troops early on was a much larger challenge than fighting Reaper forces.
The weapons modification aspect is back, though it's far less complicated and doesn't involve any inventory management at all. The only downside was a lack of diversity when it came to customizations, as far as I could tell. They were very basic - longer barrels for more damage, armor piercing modifications, scopes, greater thermal clip capacity, etc. Polonium rounds didn't make a come back, like I'd hoped, either, but that's a personal peck. Armor modification was less spectacular. You could deck out your existing armor with modified parts that altered the armor effects, or you could purchase other sets of armors that couldn't be modified, that came with a suite of their own effects.
I was surprised with how seamless Bioware made the customization of interaction with some parts of the game. Conversation pieces that depended on variable decisions made in prior games (even things like who you slept with) seemed to flow pretty naturally. It also left me aware of how there's probably a whole bunch of dialog and other things, that each unique player will never see simply because of the choices they've made. A lot of the conversations have tensions and emotions that feel palpable, and I enjoyed swimming through them.
The worst part of the game, in my opinion, is what is required to earn the best possible endings, which necessitate a galaxy military readiness rating of 4000 to 5000. These ratings are only possible by playing the multiplayer game. For everyone who bolstered Mass Effect *because* they enjoy a good single-player experience, it feels like a creative stab in the gut to force them to fuck around with multiplayer hookups (something they may not like) to obtain a desired ending. Without engaging in the multiplayer game, the only outcomes possible involve the destruction of Shepard to save the galaxy. I despise "hero must destroy himself to succeed" themes, so this is especially odious to me.
The side-quest system is pretty slack. Side quests add to your readiness rating and lengthen the game, making it more interesting. Most side quests are picked up by overhearing conversations on the Citadel (pretty much the only place in ME3 where you can get out of your ship and roam around to talk to folks, now). Finding most minor side-quests involves going to a planet and scanning it and launching a probe. Everything else is handled off-screen. The difficulty lies in the Reapers zeroing in your position the more you "ping" a system with your scanner. Contact with a Reaper ship in the solar-system navigation screen is an instant-kill. The side-quest management system is dreadful, as well. Coming fresh off of Skyrim, which updates your side-quest log to show the next task to be performed to complete the quest, ME3 doesn't update the quest menu based on how many steps you've already performed to complete the quest. Due to the impersonal nature of just launching probes at planets and receiving notifications that we've picked up "things", I often forgot which items I'd already picked up for which existing side-quests. So my side-questing devolved into me just going out to systems I hadn't fully explored, yet, scanning everything, picking up as much as I can before death-by-Reapers, and skittering back to the Citadel to run around the same goddamned rooms to see if there was anybody who needed the things I'd picked up. This was a very sloppy way for the game interface to manage side-quests, and it put me off a bit.
I didn't feel this was quite an issue in ME2. I often received quests in gigantic bursts that were hard to manage, but if I slowed down and went through them methodically, I could take care of them. I suppose Bioware wanted to create an environment with a very real sense of urgency, with Reaper forces making their moves, closing in here and there, and I guess on that front they did a good job. I definitely felt more "rushed" about things in ME3.
Other bad things include some aspects of the writing. Well, ME writing has always been that way. The ME universe is the one your grade school teacher told you about. It's the kind of world where most, if not all conflicts, are the result of unfortunate misunderstandings that can be easily solved if both parties are properly appeased and cooler heads at the leadership level prevail. The ME universe is one where extreme freedom means legalized slavery, and the like. It's a world where megacorporations run out of control in some areas. It's a world of cliches in a lot of ways. Sometimes aliens seem way too human. It's a world where solutions to old (and very real) problems are vilified, despite the horrible fates we'd suffer if they weren't enacted. It's a world with an alien species comprised entirely of sexy females who just happen to share the exact same body shape as female humans (as opposed to say... female Turians). I wouldn't say the game writing is a leftist screed, but it does have overtones of modern cultural zeitgeist, where progress comes in the form of regulation and freedom solves nothing.
Overall, fun game, great epic, but disappointing conclusion given the multiplayer requirement for a more desirable ending. I may give the multiplayer a shot sometime, just to get my readiness up to a bare minimum required for these endings. But I'm not feeling quite so masochistic, yet.