Really glad you can see the beauty of the old design again, dondan!
I might be a little late to the party, but:
- I prefer the side I/O and i don't think that breaking stuff sticking out from the side is or it should be a real concern. First of all front I/O it's an accessibility thing, so don't have to go all the way to the back of the case to stick that thumb drive you wanna use for few minutes. Second, i can't see anyone buying this beautiful case taking pleasure from seeing cables and USB stick's (or other things) sticking out of the case like a weird octopus.
- The current case feet look the best for me.
- Motherboard standoffs on the side panel does not sound like a good idea, especially if that side panel is mounted in a traditional way, like the front side panel. There is a very good chance that it will warp under the weight on the motherboard+cooler if the only points of support for that panel are 4 screws on the edges of it. I don't think you can install standoffs on the side panel without leaving some marks, if you look close at the side panels of the A4 you can see the uneven surface leveling where the push pins are mounted. Not to talk about how weird it would be to take that panel off with the motherboard and all the cables dragging it back. If the panel would be mounted on a semi-permanent fashion then it may work but then, again, will hurt the flexibility of the case, you won't be able to rotate the layout that easily.
I hope my feedback is constructive for you.