You're not getting a response because you are asking too much, and only a small handful of people on these forums can address something of this magnitude.
1.Fury Cutter. The move doubles in power after each hit (up to 5). Can you give scizor the item that when held always makes multi hit moves preform full hits?. You get increased damage from technician and increased damage from it being bug(i think).
It's horrible, you shouldn't be wasting your time doing this, and really defeats this Scizor's purpose of simply coming on special Attackers, trapping, and OHKOing them, it cannot sweep and no one would be stupid enough to not have a bug resist or let you keep doing it repeatedly enough to get stronger.
2.U-Turn always seems like an amazing move and much more preferable to X-Scissor... but is he fast enough to utilize it? IMO its only worth it if he can go 1st and do dmg while u swap to something resistant. Yes, i know it all depends on what im fighting but can you give me a general idea?
This is what you want, U-Turn is STAB, and you can use it immediately to scout your opponents team, or for Magnezone who will come and ruin it's day, it will also put you 1 step ahead of your opponent.
3.Is roost a more useful move based on scizors defense and typage or should i go all out attack? I dont want to make a swords dancer but i'm unsure on this slot.
Roost or Light Screen are the only sensible options here. You should test both out and see which works better for you.
IN Relation to #3: I dont know what EVs will preform best but the main reason i was drawn to "it's a trap" was the fact that they did (176 HP / 100 Atk / 176 SpD / 56 Spe).
1st of all you shouldn't use this spread since it is for outspeeding Shedinja and the very very old Magnezone, both of which you will almost never see in OU.
I have a spread in mind but I will withhold it till the end of this post.
However, I intend to focus my EVs to balance out w/ what my IV's lack. And in terms of IVs i bred over 100 scyther, got ~23 adamant technicians and the seemingly best 3 had the following IVs.
14 HP/ 31 ATK/ 22 DEF/ 19 S.ATK/ 28 S.DEF/ 19 SPE
18 HP/ 15 ATK/ 31 DEF/ 8 S.ATK/ 23 S.DEF/ 28 SPE
3 HP/ 31 ATK/ 31 DEF/ 8 S.ATK/ 1 S.DEF/ 28 SPE
I definitely wouldn't use the 3rd one, especially since the whole point of Trapper Scizor is to be bulky, and the 3rd one is the least bulky of the 3
You should be using the 1st in my opinion.
And to compensate for the bad IVs your EV spread should look something like:
96 HP/ 104 Atk/ 252 SpD/ 56 Spe
The 96 Hp gives you optimal Leftovers recovery, coupled with max Special Defense will allow you to survive a wide variety of special hits thrown at Scizor, and the 56 Speed Evs with your Speed IV, is enough to outspeed 4 Speed Vaporeon, but if you don't want to outspeed it, then you can always feel free to move all of those EVs into HP or Attack.