Thats what I mean the decimator would sort out pedal noise easily and any hissing noises but its the guitar and amp which will be the problem for that loud ringing in between notes that's where a gate comes in.
Ive always played very loud and whilst I was playing thrash I never even used a noise gate but that must have been because I was playing so fast all the time theres no time for feeback but when youre not going mental all the time I guess that's where the squeals come in and in my last band which was brief was a brief experience the music rythm wise was much slower and feedback was a problem but forleads which were faster it was fine.
If you dont have any thing in your loop sounds like an ns2 at the start and a decimator at the end would be perfect but of course experiment as there arent any rules. Youll also find you wont have to set your decimator so high just to cut down on pedal/preamp noise.
I actually took the plunge with 2 noise gates after seeing bullet for my valentine use 2 boss ns2's (Shudders at BMFV but decent guitar tone for an emo band) and Misha Monsoor uses 3 noise gates an ns2, decimiator and one built into his amp.
I just use a guitar, amp, overdrive pedal, delay pedal and 2 noise gates.