In regards to Chip ram usage, I use OS 3.9 with BB4, and with the "icon to fast" option plus PeterK's icon library
Peter K's icon library is great, but even with 3.9 you need to add two things:
WBCtrl IMT=FAST
(WBCtrl is a separate utility)
and
LoadWB SIMPLEGELS
That's what I use to put everything in fast memory. Can't recall where I found the original tip, but there's a mention of it here (from a quick google search):
http://ftp://ftp.cs.tu-berlin.de/pub/aminet/docs/help/OS35FAQ.txt
