i would sleeve it, once those wires get warm or hot the sticky part of the tape is going to get moist and the whole this is going to be a mess (sticky)
Looks better mate but at the end of the day you were never going to have any problems with the wires causing heat issues as you have plenty of breathing space in there, but you probably did it more for looks than anything? good job though
ive got a micro atx board aswell, and like you i was unaware at the time as the spec was great thats all that mattered, but as it happens ive upgraded it nicely and it hasnt held me back at all so i dont think theres any real disadvantages