That is pretty much the bottom line. The only update following that is that I think that I found what the issue is, just not where exactly things go wrong.
As for the weekend thing: what I meant was that I'd work on things over the week as much as time would allow and then try to finish it over the weekend. Everything but Schematica is already on 1.9, hoping to get Schematica 1.9 ready as soon as possible.
I intentionally avoided the forum thread, to waste as little time as possible. Posts can take anywhere from 5 to 15 minutes to reply to and that time is better off spent at updating the mod.
Side note/question: has anyone experienced stuttering in vanilla on world load? I have noticed that in 1.9 vanilla and Forge the FPS drops to 20-30 while loading/generating the terrain and goes back to 110-120 after the loading is done (limited to 120 in settings). This is a bit concerning as this could potentially directly affect Schematica's performance when loading up schematics.
yes they changed something in 1.9 which casues the chunk loading and generation to be very resource intensive , it causes invisible chunks and serious lagg . reducing the render distance is a crude way of countering this
i think https://bugs.mojang.com/browse/MC-98994 they might fix this in 1.9.1 .
b.t.w. <3 your mods , i am saving up for a new pc else i would love to donate you some beer