Where to start on BR blue...
Well, for me, back to my teenage days in Devon & Cornwall - was always pretty dismissive of the duffs, which is what we do have... so a 50 (or 4: unrefurb, refurb blue, LL & GW green

), some decent 37s for the clay, and some Peaks for the long- distance clay & NE-SW passenger services. Don't yet know what the DLC 31 and 33 are like, but used to see both at Exeter on a regular basis.
Exeter was always a good day out - bit more variety, especially with the 33s from SR and occasional 40s on the Meldon stone trains. Missed the 25s in Cornwall, but always liked the type.
So out of that lot:
31 & 33 - will buy at some stage
50 & 37 - current routes fundamentally flawed without. Would buy a re-releasd 50 straight away.
Peak - like the 31 & 33. Would certainly buy, but probably not straight away
(And no, google is not my friend

)