I do triple science and two languages (French and Spanish). I am very glad I did triple science, and it's good "value for effort" in my opinion. For example, with double science you still have to do the three courseworks for biology, chemistry and physics but at the end you only get 2 GCSEs out of it. For triple science you do the same coursework but get 3 GCSEs. We were also given the chance to redo some coursework to get full marks as we had more time than the double people.
Also, there is not a vast amount more work to learn for triple science for the actual exams than there is for double, yet you still get a whole extra GCSE out of it. We also seem to have much more time to learn and revise eg in chemistry we have already finished the syllabus and are revising comfortably whilst the teacher says that the double chemists are struggling to finish on time for the GCSE.
I often think how glad I am that I did triple science as it was the option that gave me the least work possible compared to other subjects I could have done, and it is in my opinion more highly regarded. Like when I went to a 6th form interview once, I spoke to the teacher involved with medical uni applicants and he was very impressed that I was doing triple. Most schools don't, so you'll stand out.
I actually feel sorry for my friends who do double science and say, geography or food tech - sooo much more work.
If you think you want to do A Level science, triple does prepare you well and give you a bit of an advantage. So it's good for scientific careers too. Science is always highly regarded and you can't really go wrong with it. (Assuming you're okay at science).
I also like Spanish and I've found GCSE language is not too hard, but if you find languages hard, maybe you should think about it.
If it was me, I'd do triple science, no question...Though, Spanish is still a good one to do.
Do you find science interesting? If you quite like it, you should be fine.