The mega customisation of ME1 is really annoyingly too big. Hundreds of items that you have to compare and decide which one to use, I mean what the hell, I want to spend my time playing a game, not deciding "how" I'm gonna play it. But I agree with you in the mining stuff. Quite fun, but gets old fast.
There's not that much to compare, really, but that's the bad thing. I mean there's really only a few models of everything with numbered versions, where a higher number presents a batter variant of the same thing. So if you liked Onyx V better than Guardian V, then that armor suits your playing style better and you'll likely just keep getting better variants of that. The problem was, in my book, the completely generic nature of all items in the game - just a few numbered series and that's pretty much it. You definitely didn't need or have to spend a lot of time analyzing the stuff just because the system was so oversimplified and generic. Compared to that, I actually prefer not having an inventory the way they did it in ME2.
Overall, I found ME2 to be the better game with a lot of streamlining and improvements, and a few steps back. The two most significant steps back, for me, were the new ammo system and the mining mini game they replaced the Mako with. In ME1 all weapons cooled down automatically and this was the mechanism forcing you to let go of the trigger every once in a while. In ME2 they tried to make the weapons seem more like today's guns so they wanted an ammo system. They couldn't reintroduce real ammo back after ME1's weapons as that would be a major technological step back and a plot hole, so they had those heat sinks that you have to eject to cool down the weapon. That's all well and good but it makes no sense that this is the only way of cooling down a gun - if you don't eject the heatsink your assault rifle will remain overheated until the end of the universe. That makes zero sense to me and while the action is fun, the weapons make no logical sense and feel like a technological step back compared to ME1.
The other step back was the mining thing. In ME1 everyone complained about the Mako sequences being boring. True, there was really precious little to do when exploring random planets with a Mako, and even if there was some side quest on a planet it was generic, short, and took place in a recycled building you saw 50 times before. Ok, so no wonder people found this boring; the way forward here is making more different sets for the quests to take place in, and write more interesting reasons to go planet hopping in a Mako. The basis of a very cool system was there; and while I understand that doing what I'd like to have seen would be a large amount of work, I find it was a shame to see the Mako replaced by a boring but thankfully short mining mini-game. It wasn't so much fixing a problem as trying to drive around it. I prefer option 1.