What about spells? Currently I have fireball 2, armor 3, blind, mind wipe, heal 2, and aim 2. Should I swap blind or mind wipe out and get lightning ball?
The lightning ball spells aren't bad, but I prefer the lightning bolt spells, since they cost fewer AP. To cast lightning ball without leaving yourself in the open or having an awful hit chance, you really need either Haste or extra AP from drugs.
Mind Wipe and Blind are fine choices, but I prefer buff spells to disabling spells, since they're more accurate. Even so, disabling a key enemy (i.e. mages...) can really turn the tide of a battle.
Don't overlook the Flamethrower, Manaball, and Mana Bolt spells, though. Fireball inflicts 'on fire,' which lasts longer but it's reduced by armor, while the mana burn debuff bypasses some armor, so even though it doesn't last as long it might wind up doing more damage. Flamethrower's damage is reduced by armor, but it does so much damage (I think the base damage of Flamethrower 4 is around 40?) that it's still a solid spell for sniping.
Am I stuck without any cyberware?
Pretty much, yeah. Cyberware reduces your essence, which increases how long it takes your spells you recharge. Every point of essence lost adds 1 round to the time it takes for a spell's cooldown to end. If Heal 2 normally takes 1 round to recharge, and it's cast by a character with 3 essence, it'll instead take 4 rounds to recharge. I mean, theoretically you COULD have cyberware on a magic user, but it would have to be some damn good stuff...
If I picked up just a cybereye to increase hit % would that hurt my spellcasting?
Yes. Essence is rounded down to the nearest whole number, so as far as the game is concerned, 5.9 essence and 5.0 essence are the same thing.
Any advice for the APEX mission on very hard?
Cheat. Seriously. This section of the game is buggy as shit and the developers have acknowledged it and pretty much stated that they don't care. I think the cheat menu is either Ctrl+F1 or Alt+F1.
Why is Blitz such crap, is there any way to improve him?
Blitz is fine, but he's not stellar. With a couple buffs he's noticeably better, however. Sniffer, for instance, will increase his accuracy (and the accuracy of his ESPs) significantly, and make him way more effective while he's jacked in, even if you do have to refresh it periodically. Shield, likewise, will make him a lot more durable.