Deciding...A-level options...

Hello,I would like to do Medicine at Cambridge/imperial college London later on...
I am currently at the start of Y11...I am concentrating on my GCSE's but we have to pick our A-level options very soon...(We are allowed to pick 4-6)...

Is the following suitable for medicine:

A levels:
1)Biology
2)physics
3)Chemistry
4)Mathematics
5)Further mathematics

Are these good?If i were to do 6,what would you recommend as the sixth one...

Also currently as the START OF Y11 this is what i have done in prep. for Medicine...

Extra- Curricular - Non medicine Related…
1)Piano-Grade 1,2,3,4 and doing 5
2)Drums-Grade 3
3)Music Theory-Grade 5
4)DofE-Bronze,doing silver
5)Table Tennis-County
Extra- Curricular’s-Medicine Related…
1)Blogging about Medicine
2)Medicine courses
3)Wider Medical Reading…
Work experience…
1)4 Months British Heart Foundation
2)Applying for hospital work experience…
3)Applying to care home for volunteering

Is this good?
What else can i do to improve my chances of being accepted...

In terms of grade,i am predicted t get 9A*'s and 3 A's in University...IS THIS DECENT?

Thanks....