This is a debate that's gone round and round in circles for years. We tried regional events, what happened is the same core of competitors travelled to Scotland or Eire or Wales, and one or two locals joined in.
With limited resources we decided to throw everything into one big event, as most of the European chapters do. We had a couple of really good events, but sponsors are hard to entice in an economic downturn. The disadvantage with one event is if you can't make that date then you miss the whole year, although anyone who is serious about competing will probably travel to Sweden or Germany and enter their comp too, since the top competitors are usually travelling subby climbers it's not too difficult to work your way around a few events in the year.
My thoughts for what they are worth:
The isa events have an image problem, there is a general feeling that comps are elitist, that there is a group of professional competitors who don't actually do any tree work and just train for competing, and that any normal working climber who entered would be made to feel like an idiot.
The professional competitor thing is nonsense, everyone who enters is a working tree climber, there isn't any financial incentive to win comps so unless you had a lottery win you need to work, and it's the same work everyone else does.
When I went to my first event in 2004 I was using the same kit and techniques I had in college, willans harness and a prussic, I was painfully slow and couldn't footlock to save my life. No one ridiculed me, I did feel a bit like a sloth but I came away with a vt and about 3 years of progress in a weekend.
There obviously are things that could be done better, but please bear in mind that all of the organisation is done by volunteers, who have their own jobs or businesses to run as well, and it takes a phenomonal amount of time to put an event together. There is no funding from the isa, the tcc are self funded through entry fees and sponsorship. If you want big prizes then you need big sponsors or big entry fees.
A single comp held at the same event every year would help with promotion I think, people need to know in advance when and where it's going to be.
The introduction to comps weekend we had at Kibblestone was excellent I feel, it could be replicated on a regional basis but would need people to organise, not much harder than a rec climb meet up. The days of having 4 uk comps are long gone though, there just aren't the resources available.
On a brighter note though, despite the perceived problems in the uk, for a tiny nation we are incredibly successful in the European and world championships. Just think what we could achieve if more than 17 people turned up to the uk event......