Getting her booked means using Epic Skills Books to upgrade her skills, since you want 100% Decrease Defense and 100% Block Buffs chance,

Her artifacts should focus on getting her faster than your damage dealers, and with Accuracy enough to land your debuffs in both PvE and Arena. So think like 200+ Accuracy for level 20 dungeons, 250 for 25, and as high as you can get while being decently fast (think 200 or 220 speed) for Arena. After that, build for survivability by maximizing HP with 3k+ defense.

OFC this is all aspirational... at first, get as much accuracy as you can while having her faster than your nukers.

Also - while the conventional "focus on stats, don't worry about sets" logic is almost universally applicable, in the case of someone like Uugo, I think I'd make an exception. Perception is an *excellent* set for her, and is almost always going to be better than the alternative, since it gives both speed and accuracy, both of which she needs.

I only have a perception helmet and shield. Thoughts on what to use for the rest?

I only have a perception helmet and shield. Thoughts on what to use for the rest?

gloves with hp% or defense% as the main stat, chestplate with accuracy, hp%, or def% as the main stat, boots with speed as the main stat. speed and accuracy are the most important stats by far, with hp% and def% coming in a distant 3rd so look for those substats on your weapon, helmet and shield (the same goes for the other 3 pieces, but in their case the main stat is of greater importance). 

as always, don't concern yourself with what sets the pieces come from. the perception pieces you mentioned might be worth using at the moment (depending on what else you have available) but you'll want to replace them with 5 or 6 star gear in fairly short order.