comp sci gets interesting in GCSE, however, it does depend on the exam board how academically challenging it could be, aqa and edexcel require you to learn a specific coding language, while ocr doesn't. my friend does art and the workload is intense from what i've seen, however they do require you to try many different art styles (which you don't like) but it does seem quite interesting so consider whichever would help you at alevel.