All very informative, this. Thanks guys. I had a basic understanding of RF before this but now much better.
My longest exposure was 25 seconds, if I recall, using Fuji Velvia (attached) to photograph a St Ives cobbled street. So I'm not used to thinking beyond that.
As for home development....an interesting point. I actually have an enlarger (Ilford 400HS multigrade head) with a fantastic Apo Rodenstock lens. I have some dev tanks, red lights, etc etc and have, in the past, produced some prints with it and I really enjoyed it....the only problem is somewhere to do it now, since our kids came along and occupied the room I used to do it in! In addition, I don't have a room that I can sufficiently darken (I have tried in one room but it was always a major hassle to get it dark enough) and, in the past, despite practising, I screwed up quite a few rolls of film with photos I had hoped were going to be good. Based on my failures, I thought "Oh well....I'll just send to the lab - it's easier and at least I won't screw up my films" and then any "keepers" from the proof sets I'll send off back to the lab to be hand printed.
I know the next suggestion will be to buy one of those little tents to do the film tank loading etc, but I still need somewhere to do the printing. And then there's the frequency...developer goes off once opened of course, after a few months (if kept in an airtight thing). I don't do enough photography, really, to use up the liquids I buy in time before they go off. 8 months ago I poured 5 litres of developer away that had gone brown and manky 6 months beyond it's use by.