I'm in the same boat. My rear fan is dead (easy enough to fix). I love the case and want to use it for my next build, but I know the 200mm fans will not hold up for many more years.
the colors and speed control are nice, but I'm willing to loose them.
the front 200mm fan is only 3/4"-20mm deep!
the side 200mm connects to a specialized plug.
top 200mm should be no problem.
it looks as though a pair of 120mm's wont fit in the front either.
thermaltake replacement parts do not embiggen me with a lot of confidence, nor can i find a top fan replacement.