I fired up TimeSplitters 2 for the first time in like two decades and immediately went 
at the aiming controls
Firing from the hip, there's no crosshair on the screen, which would be fine, but instead of a zoomed-in aiming mode or iron sights, aiming your gun roots you in place and gives you this light gun game-like pointer crosshair. Usually, aiming in an FPS game decreases your sensitivity to make it easier to make finer adjustments but this is the opposite. The crosshair is essentially a super sensitive mouse cursor that you control with a stubby little thumbstick, and it feels terrible to use.
Halo had been out for almost a year by the time TimeSplitters 2 came out so why didn't they just crib Bungie's homework 
I quickly went back and checked TimeSplitters: Future Perfect and sure enough, it just had a regular Halo-style crosshair as the default, called "fixed crosshair" in the options, with the old control style called "moving crosshair." I guess by 2005 Halo had established its control scheme as the de facto standard for console FPS controls
Timesplitters aim is taken directly from goldeneye and perfect dark. Personally i find it significantly more intuitive and they were my favourite fps games as a kid to play. It was in itself a method of making single stick FPS playable, precise aim is for sniping and stealth headshots otherwise make sure the enemy is in the center of your screen and fire. Although i can imagine this is like me liking tank controls so...
I found my right arm going unconsciously to my mouse whenever I used the aiming mode. It feels like something made for a mouse due to how sensitive it is. With full-auto weapons, shooting from the hip works okay but the beginning of TS2's first level requires stealth and accurate headshots with semi-auto weapons and it's not a good time
I also love tank controls... at least in survival horror games. The first two Onimusha games have them in a melee action context and it wasn't the best experience 100% time
Yeah the zoom controls i will admit are just plain bad. Don't think the first level actually requires stealth though it just makes it easier but you can run through and trigger all the alarms. Not that it helps much.
I think out of the fps on the ps2 at the time it was still the nicest feeling as competing games were medal of honor, killzone, nightfire, agent under fire. Which all felt clunky to me