I disagree with Gromnir's wording, but not the message. Slow level progression wasn't the problem, the problem was the level CAP. Maximum level of BG1 with TotSC was 8. For a player like me, thats plenty, I prefer low-level adventures.
Unfortunately the vast, vast, vast majority of players prefer [lame] 'epic' levels, so they can pack in all the feats they possibly can. *Shrugs* Different strokes for different folks.
P.S. The 'lawn-mowing' areas in BG1 were awesome. I loved wandering around the maps and stumbling across encounters.