Am I the only one who actually LIKED the interface in SS1?
GUI was good, fixed binds and control methods were shit.
I can't really agree. Ignoring holes in the premise SS2 had better logical succession of events. It also had much better atmosphere.
It did disappoint mechanically, however:
First, there was no feeling of enhancement supposedly conferred by your cybernetics - in SS1 you could plug so many different things into your brain giving you shielding, improved senses and extra information, improved locomotion, cyberspace access (although cyberspace sucked) and so on. In SS2 you have... goggles. Yay. Zey do nothing. You can't even play games in your mind, you need a fucking gameboy for that.
Second, the hard skill restrictions on using a lot of stuff (weapons, armour) made no fucking sense - a grunt not being able to use not only a fusion cannon or some exotic weapon, but even an AR or basic shotgun or pistol? Little kids used as cannon fodder in Africa can use assault rifles just fine without having zee goggles plugged into their eye-sockets.
Third, SS1 had more diverse and less redundant arsenal. Energy weapons fired actual beams, laser rapier actually used energy and so on. It was also amplified by much more meaningful resistance system - some weapons could fail to damage enemy altogether not just because of wrong damage type, but also by failing to get through the armour.
Fourth, there was a lot more stuff to fiddle around with - energy weapons had continuous power settings, you had a lot of explosives you could throw manually, with settable timers and fuses, you had patches, you had usable cameras.
Fifth, EMP grenade effect was awesome.
Psi powers and radiation mechanics were nifty in 2, though. Can't say anything bad about research, repair, modification and having to maintain your weapons either (also hacking the damn turrets).