I think that there should definitely be some sort of system in place similar to how it used to be so riders have a rough idea on the severity of the events. This used to be closed to club, restricted to centre, open to centre, national etc etc. Obviously this is unnecessary and can be simplified massively nationwide and not just in each centre as I know this is a problem all around the country.
Closed to club - straightforward sections with a variety of routes for abilities. Should be pretty easy for the top riders on each course. These are where you would go for your first trial.
Centre Trials - tougher sections on all courses but still with the variety of routes
Centre Championships - basically the same as centre trials but this varies from round to round and is venue dependant.
Nationals - doesn't really need explaining although some nationals do have sections which are too severe at times but this is not every section.
The idea is that the new riders progress upwards if they want to. If the riders don't want a challenge then they can stick to doing closed to club trials and at least they know what they are getting before they go. No point turning up to a centre trial and moaning its too hard if the severity is above them and they know it will be too hard. I think the ACU could get onboard with this too so a system is brought in across the board so it makes it easier to understand for all riders - not just the newbies.
Slightly different but yesterday my club, Sheffield & Hallamshire, ran a charity trial with only one route and 16 sections per lap over a 4.5 mile course. We had 90 entries which was unbelievable to say there were 5 other events on in our centre alone but also shows we must be doing something right.
The sections ranged from usual white route sections (very easy) to expert sections with 3 graded climbs. The idea is that the usual white route riders will struggle on probably half the sections but they only do 2 laps as the inbetween going can be tricky for them. We gave a choice of either 2, 3 or 4 laps and the experts and the majority of the good clubmen (middle course) riders did 4 laps. I think the overall winner doing 4 laps lost around 10 marks doing 4 laps of 16 and he had to ride well but there were no sections at all that an absolute beginner couldn't have a go at. Obviously it won't have suited everybody but it was something completely different to normal and yes a few sections churned up a bit more than expected (especially with 90 riders) but there were no real moans and everybody had a good day out on the bikes. I'm not suggesting this is perfect by any stretch of the imagination but it worked well.
The biggest problem I see is that there is no challenge and no thought in the sections at a lot of trials. Nobody seems to want to lose marks anymore which I find is very odd seen as the event is called a trial. Would you expect to turn up for a round of golf if you are a newbie and go round on par or under par? No you wouldn't so why should it happen at trials! It should be a challenge but shouldn't be dangerous at all. That's my opinion anyway!