I just did my Thinking Skills AS exam. And i would say that it is much easier than English Language. English Language is pretty hard. Oh but then again, both these subjects dont like actually provide any weightage to your uni application. The maximum it will do is seperate you from People for example if You Have 4 A's and Another A in Thinking Skills compared to a guy who has 4A's and a B in thinking skills, u would be more preffered. However, unis dont actually recognise it as an A Level Grade, so if they like ask for like 3 A's, those 3 A's must be not taking into account Thinking SKills