Nice setup man!!!!
Everything looks good to me. I like to run mixed bulbs. Right now I am running 4
ushio 600 MH dropped vertical and 5 1000w horti HPS vert. So the middle bulb of the 9 is an HPS and then the 4 corners are MH.
Right now the heat is shitting on my grow so I HAD to use 600's. I prefer 1k all the time. I will run all MH the first 3 weeks of bloom, then go to HPS for weeks 4,5,6 then back to MH for 7 and 8.
Best thing to do is take notes and try not to change too many things at once.
Flip size completely depends on strain, spacing, ceiling height, etc..
I would say flip no bigger than 14-16" to start on the coco plants and get your trellis in there to bend them down as they stretch.