This is what I was thinking as well. I think you and more of the forge big wigs should really be vocal about this issue. It sucks. It sucks for core maps. It sucks for BTB. It sucks for Infection, and it sucks for mini-games. This is something that is having an effect on every avenue of forging.
The frame-rate isn't going to be fixed. http://teambeyond.net/forum/topic/5443-halo-5-guardians-discussion/page-5345#entry875463
Scripting rotation test with a simple setup consisting of a simple primitive block welded and a phantom, below are the results: Forge Customs
I have two maps built currently that o think run smooth... Only thing left on em is to play test... One is a low grav free for all in space called GlacticKnifeFight both a map and game mode... The second is a team based map that will hopefully have multple game modes ie CTF, slayer, etc which is called PelicanDown which is inspired by maps like Blood Gulch and Woodland... I have plans for a canyon style map on an island as well as a remake of a space outpost map my buddy and I made for Halo 4 but those may not happen for a while
Anyone with some kind of connection to 343 want to report the Waypoint issue? I have tried to get it noticed multiple times now and this is going to be my last attempt before I let it go. Other people are going to bump into it within the next few weeks once they start trying to share files that use the minigame mode. I am hoping that their internal filters simply aren't searching for those gametypes--which should be a simple fix. Link with the information again.
polygons aren't the only performance impacting aspects of graphics... these newer materials must be either less compressed or in some way more difficult to display. they certainly look more complex than plain "metal". also, keep in mind that the shinier we make our textures, and the use of the new "shilak" might cause those shiny effects to negatively impact as well. EDIT: overlays probably play a part in this as well, as its essentially a 2nd texture applied to a piece, and one with transparent areas. that takes power to render that wouldn't otherwise be needed.
And here I was excited to finish a couple of my maps because I had heard they were addressing these performance issues in this update. Alas. Back to playing Overwatch. If it had a map maker even close to the level Halo 5 has I'd probably have sold Halo by now.