I have been thinking about making this thread for quite some time. I have some suggestions for Skyblock. Maybe bring back Villagers but with a limit on each island? (if that is possible) Soulsand and Glowstone in the shop? Allow Grass and Mycelium to be picked up with Silk touch? Leather able to be sold in shop? PVP Arena? Dirt/Grass/Sand/Mycelium in shop? Redstone in shop? Add more suggestions if you feel more need to be added. Yes, I know some of these suggestions are stupid.
You can get glowstone/soul sand from your nether island, but everything else on this list I support. Also enable snow and iron golems.