concerned with subject choice suitability for cs

It's fine, the only possible issue might be a lack of A-level Further Maths for UCL, although still worth applying. The others I don't anticipate would have any issues.

You don't need to mention any of your A-levels in your PS specifically and I wouldn't really suggest it - unis know how different subjects do or don't relate to the subject you're applying to, what they don't know is why you want to do that subject (and giving potted descriptions of your A-levels doesn't tell them that).

whilst this is very fair enough, ok. should i mention something like a "craftsman attitude" in my personal statement, since i do product design?

so i do physics maths and product design at a level and am predicted AA*A respectively. and am concerned if my uni choices will dislike the fact that i do product design and not some self-harm inducing subject like chem. current uni choices are
UCL
Sheffield
KCL (maybe)
Bath
Surrey
(Loughobrough if i dont choce KCL)
I am fit for the contextual offers for all of these unis.
Any advice? should i try include product design stuff in my personal statement to make it sound as its going to help me with cs?