Geting there, alot larger then the first one
how stiff the frame is?
The frame itself is not that riggid, but the coming enclosure will add support.
One of these days, I may put together a delta printer with the electronics in the top an a power supply that is smaller than an ATX power supply in the top as well. There is this big wasted space the shape of an upside down pyramid in the top of deltas and I would prefer to keep my electronics far from my head bed.
Alternatively, I suppose the area to the side of the display or next to a tower would be an ok place for electronics.
Good luck with the enclosure. I hope it makes it nice and stable for you. I wish I had the skill to make a 3D printer from scratch. I am still buying upgrade parts for my first delta. I am going to try to add a 2nd extruder for course infill of possibly lower quality filament and see how it works out for me.
I wonder if a cross-brace per side would do the job.
@NathanielStenzel my first build took me a year to complete, i had help alongside and u get skills if you have a passion and dont give up, so i say dont think, build 
@Mark_Fairbairn the delta twists so yes a cross brace one 2 sides would make it rigid. But u have to take in to acount that the platform moves in cirkles, so the support must stay clear from it. my first printer is round, this one will use a hexagon shape and walls for support.