I did a chemistry degree, in Manchester, (Londoner, i avoided Imperial and all London unis)
It's a bloody brilliant degree
I loved it all. I am also pretty artsy - i paint and draw, and did philosophy, art, physics and chemistry at a level. i think an arty lean is an advantage for a science.
In terms of post degree - I work in advertising - i looked into PHDs at Imperial actually, but the ones i was interested in lost funding. Most of my friends from uni work in either finance or software/programming. A few have gone into actual science, not most though. It is very versatile. A sandwich year is great but only if you know, or think you know what you want to DO imo.
I think my degree gives me a real edge at work - i can deal with huge reams of data, analyse outputs quickly, write clearly, concisely and fast, and i don't panic if there is a fire - there is not a job going in which these are not advantageous!
It teaches you analytics, problem solving, writing, a healthy scepticism of your own results and a total lack of fear of numbers, and is great fun.