I'm taking it that you'll be carrying Maths and Chemistry onto A2. Shall you be dropping one of Biology or German though?
If you look at the course outline for universities offering Chemical Engineering, then you'll find that they do have a design aspect, but it isn't a majority aspect of the degree and so shouldn't necessarily have you discounting the course solely for that reason.
For example, here is the outline for Chemical Engineering at Manchester University:
http://www.manchester.ac.uk/undergraduate/courses/search2013/scholarships/course/?code=03848&pg=2You'll have Chemistry graduates doing well, and also not doing so well. You'll have Chemical Engineering graduates doing well, and also not doing so well. I've got nothing to back it up with, and it is probably because I've read the same things as you, but I would say a Chemical Engineering graduate would have better prospects (I am applying for Chemical Engineering though, so it might just be my hoping)
If you like Maths and Chemistry, then there are many degree choices available to you. A quick search on Google brought this up:
http://www.southampton.ac.uk/chemistry/undergraduate/courses/f1gc_mchem_chemistry_maths_combined.page I'm in no way saying this is for you, but it is just showing you the options available if you look into it.
I'm not going to assume anything, as it might have been because you felt German broadened your subject choices and that taking five subjects would've been too much. However, do you like physics? An understanding of physics will be needed for Chemical Engineering.