The quality of your writing doesn't really need to be a determining factor in what kind of paid membership you have here on the site. A far better metric for that would be what features you use most often, and what level of membership can provide that for you. If you primarily write books, being able to create a lot of book items (or a lot of individual static chapters) might be useful to you. Don't feel pressured to buy a level of membership you don't need though!

Yes, a member's financial circumstances will most likely be the greatest determining factor in what kind of paid membership to purchase. There are members for whom spending a few hundred dollars a year on a paid membership isn't worth a second thought. And others for whom a $50 Upgraded Membership is a real challenge to pay for. And others still who need to raise the GPs to pay for their memberships. Everyone's circumstances are different, and members should definitely only purchase memberships that make financial sense for their situation!

One of my favorite things about WDC is how supportive this community is. I've been the recipient of a number of gifted memberships myself, as well as run fundraisers to pay for memberships when times are tough and purchasing one outright isn't an option.