Ancient History is a good essay based subject! I don't know about RE but I imagine there are essays, government and politics is good (especially if you're interested, I've heard it's challenging if you don't put the effort in), and psychology is good for getting a grounded knowledge in the subject.
If I were you, I'd ask your school's career advisor or email someone in charge of options. You could also discuss it at your a level interview if you're not sure, and if all else fails, your tutor will have a levels and a degree, so they'll know a little bit about it.
(I think the course is changing next year, but the Ancient History I'm doing is super fun but requires a lot of reading and revision)