I can say without more info.
Replace that willpower and monster and that random filler and netch juli and a monster poece for crit.
Do it.
Can't really say without more info.
What monster set bonus will you be losing? Are you talking about dropping willpower?
What content is it for? What play style are you aiming at?
If the question is 'is it viable to run 2 5-pieces and only one monster? The answer is yes (at least for PvP and most pve, can't speak for trials).
But all builds have an element of personal preference, so its always gonna boil down to trying it and deciding yourself.
Since ZOS still wont count a 2 handed weapon as two pieces of a set Staff uses are swindled out of a slot, so, would it be better for me to Place a 5pc Netch's on my MagSorc while sacraficing the 2pc Bonus of a Monster Set.
What I'm wearing now.
5pc Julianos +1 for filler
3pc Willpower
2pc Monster
What the change would be.
5pc Julianos
5pc Netch's
1pc whatever