I do History, Literature, and Classics (ancient history and ancient literature basically). Obviously all of them include alot of essay writing, however as someone who doesnt enjoy maths based or physical subjects (wood tech and art etc) this is ideal for me.
In terms of work load, literature has had the most. It is hard to judge how your experience will be though, as things really do differ between schools. I get 4 times as much homework as my friend who attends a different school, and I have many more mocks across the year than she does. Im not exaggerating about homework differences across schools by the way, she will sometimes have weeks with no homework at all and Im sat here with 5 thick articles to read, essays to plan up and write, podcasts etc. At my school, we are expected to spend a minimum of 5hrs outside class studying - some subjects interpret this as giving us 2-3hrs of homework and then the rest of it is up to the student to use as self-study, English literature interpreted this as setting 5hrs of homework which forces us to do self-study outside of the allotted 5hrs. So, your experience will change alot based on the school you attend.
NEAs will play a big part in this. Im not sure if every school has NEAs for literature and history, so check first as exam boards may differ. If you dont know, NEAs are coursework, and for essay subjects, this coursework is usually an essay. In my school, I have an NEA for both history and Literature. Some people can find NEAs stressful, however you are able to access all the resources you need and rewrite it as much as you like, but this will be done in your own time. I dont think NEAs should scare you or anything, as they can be quite fun, but obviously everyone feels differently and you might not feel comfortable having more than one NEA. Though I will say that experiencing my English NEA first, made me a much stronger student when approaching my History NEA as I already had experience.
I think how much you'll enjoy history at A level is partly based on if you liked it at gcse and partly based on if you like the content of the A level course. I adore history, however I did find the topics at my school a little annoying as neither the Cold War nor British Industrialisation are areas of interest to me (I was a little disappointed that they had no medieval topics). However, the Cold War has grown on me by now, and the NEA topic is really cool (the Civil Rights Movement in the USA 1865-1965). I would say many people overestimate how hard history is, as literature is much much harder. A levels are challenging generally, but History is not a particularly difficult one - though everyone will have different experiences and opinions.
As you are considering history and literature, I am absolutely forced to do a quick wistlestop tour of Classics, which is a combination of both subjects. Its not everyones cup of tea, and you seem confident about your decision to do Spanish, but hear me out. My combination of a levels is seen as a pretty classics combo, as all my subjects correspond with eachother, and Ive actually found the overlap of contents really helpful for my grades. However, you can also consider Classics as a replacement for History, rather than as a third option, if you become really fond of it.
The actual name for my course is Classical Civilisations, which means there are no language components. Most Classics courses offered at A level will be like mine, though some will have language topics. Given your interest in Spanish you might like the possibility of studying Latin or Ancient Greek in this subject, but I hate languages so Im happier with my course. My course has 2 texts (the Odyssey and The Aeneid), 2 poets (Ovid and Sappho), 2 philosophers (Seneca and Plato), and one history component (the most common I believe are Emperor Augustus or Ancient Greek art). I know you said you don't have much interest in philosophy, but the philosophers literally took a couple weeks each, are a tiny bit of our course, and is actually very different than how it was taught at secondary school. Rather than just going through a philosophers general ideas and theories, we got to study Plato's symposium (which is absolutely hilarious). Yes, its still philpsophy, but we get to Plato's opinion on queerness (which changes every five minutes) and his fanfic about his Aristotle, so don't be put off.
The 2 texts are 50% of the course, poets and philosophers are 25%, and the history topic is 25% (all in terns of how much time we spend studying them). My favourite part of the subject is probably the poets - Ovid is very funny. In general, the Classics course is quite funny anyway, but thats probably because one of our topics is love, which involves a fair few conversations about sex and how weirdly comfortable Ancient Greeks were with being naked around eachother. The skills needed for Classics are the exact same as luterature and history. If there is a school in your area offering the subject, I highly reccomend checking it out. If you do decide to take a further interest in this subject, I have much more information on it if you ask, but Im nit going to provide lits of detail on the pros and cons given that you aren't considering it right now.
I will be surprised if you made it this far, and Im sorry for any typos, but I hope I have helped. If you have any more questions I'll be happy to answer - Im a very anxious person and was absolutely feral for any knowledge about A level when I was in yr11.