PLA printing flaws + various issues (Advice Needed)  

PLA printing flaws + various issues (Advice Needed)

I really need advice with this printer as I'm at my wits end. I have experience on two other FDM printers and a resin printer. I've had a single near-perfect multi-color print (the Clefairy in the first picture). Virtually all other multi-color prints have significant flaws or have failed entirely. I've attempted to print Mew 9 times using two different models (pictured). All totally failed or came out flawed. The Magnemite pieces are from one of several multi-color prints that totally failed (there are several more different models which aren't pictured). It almost seems as though the PLA is failing to properly adhere to itself (see the single-color Blastoise).

We have the XL set up in its own room with a dehumidifier running 24/7. The room is always at 30% humidity and is decently hot (based on human standards) usually being around 24 C. We thoroughly clean the bed with soap and water, dry and then use glue before every single print because adherence has been an issue. Beedrill was the first print that I did and I changed no settings. As expected, there was heavy stringing (one of the antennae came off while trying to remove strings, it did originally print properly). I couldn't explain the weird mixes of black in the white of the wings and the yellow of the face. 

I looked up a guide to reduce stringing that was put out by Prusa. I enabled almost all suggested anti-stringing settings (retraction length 30 mm, distance between retraction 1 mm, wipe on retraction, retract every layer). I didn't reduce the print temps. I began my attempt at the 9 Mews. 

The first (bottom right), used PETG grid supports with a 4 mm distance (bottom right). It's a bit hard to see due to the flash, but wherever there were supports, the model came out messed up. I followed this with the large Mew (top right) using PLA grid supports at 2 mm distance. This time, the tail came off almost completely and, again, wherever there were supports, the Mew is flawed. I then increased top thickness and bottom thickness + increased perimeters. I also enabled "Detect thin perimeters". Using PLA organic supports, I made the top left Mew. Again, the tail is clearly damaged. I increased perimeters even more and returned to grid supports. This led to the shiny Mew (bottom second to the right) which is clearly damaged. I finally tried with another model, printing regular and shiny using PLA grid supports (bottom left and second from left). Clearly, both tails fell off during printing.

I finally had success with the Clefairy but this was quickly followed by three multi-color total failures (the Magnemite being one of them). One was caused by spaghetti-style stringing and another didn't realize that it stopped extruding. I've replaced two nozzles, at this point. We've simplified the prints (the single-color Vaporeon came out fine and so did the low-poly Squirtle) but we've had multiple failures on even single-color prints. Both the Blastoise (95% printed) and a coaster holder stopped printing due to snags in the spool. Both were caught within 5 minutes of the failure occurring and both were total losses.

I know this is a long post, but I really don't know what I'm doing wrong and how to make this work. The failure rate on my XL is far higher than on any of my other printers. I don't want to take the L and return it, but I don't know what to do. I really look forward to any advice and thank you in advance to anyone who read this long post and has advice to offer