In reply to clare_bear:
No idea what grade you climb, so here some suggestions for larger venues with quality problems across the grades:
Seaside - Portlethen (near Aberdeen) lots of probs, short access, spotter useful, tidal in some cases e.g. Prow boulder, Moray Coast venues Font 3 - 8's; Dumby (Dumbarton) - THE classic hardcore venue in Scotland, 300+ probs to 8B+ plus recent guide (not to all tastes as a bit 'urban', a bit polished, and a bit highball in places)
Mountains - Glen Lednock(southern edge of Cairngorms near Crieff) - 100+ problems Font 3 - 7C+, great location, critical you check access notes on UKC, midgey in summer but OK if breezy; Torridon (far NW), great venue, lots of good problems all grades plus tons of development opportunities, recent guide, can be somewhat midgey in summer
John Watson Bouldering in Scotland Guide useful as intro to lots of places but comprehensive problem coverage scattered, some useful stuff on
https://www.scottishclimbs.com/wiki/Guides and development stuff on John Watson's blog. Worth posting on UKB as well around specific venues or with general query.