If anyone is interested, you can try a practice skills test on this website sta.education.gov.uk/
They're not especially difficult imo, and if you have passed GCSE Maths and English you should more than cope, and the pass mark is around 66%- so room for the odd error, especially on the timed sections. However, some prospective teachers do really struggle with them, especially the maths- and if you are going to teach, say secondary art, do you really need to be able to do mental maths?
The big hindrance imo is that it isn't always easy to book dates- especially if you need a Saturday date because you are working or at uni. Some test centers do get busier than others, as well.
WRT the school experience, I think it's good, in the sense that it's good to go into a school (or multiple schools) before applying, so you have some idea of what is going on. When I went for mine, I was actually pleasantly surprised by the standards of behaviour, and I got a lot out of it in terms of seeing different teaching elements and listened in on some fascinating discussions about GCSE mocks in the staff room.
I applied for a shortage subject- so I expect it's different for PE or primary where there still seems to be plenty of applicants- but I had a week's experience (plus experience working with teenagers in a non-school setting) and that was plenty for everywhere I applied.
I do think it can be difficult for career changers, I took a week of annual leave to do my experience, which not everyone can manage.
It's also hard to find schools willing to have you- I was lucky to have relatives with contacts as no-one was willing to take me as an "unknown". Ironically, some schools were unwilling to take me because they didn't have enough permanent staff in the department I wanted to observe.
I think, to be honest, they don't need to make applying easier. The bursaries are very attractive, and do encourage people to apply. It should be a competitive process- if you can't manage the application, then you're surely not going to cope with the PGCE?
I think the most off-putting part of the application process for me was at interview, when we were told everybody would need a car, and we'd be expected to deal with 1hr+ commutes to placement (at Exeter the placements could literally be be uncommutable from the uni).
A lot of people my age (mid-late twenties) just won't consider teaching though- because of their perception of the behaviour in schools and perception of the workload. Until that changes, a lot of people won't apply.