I did this holiday last year and you'll be fine, Mijas is a small pleasant place and the hotel is fine.
If you decide to do all the excurrsions you'll only have one free day, they are all worth doing if you like that sort of thing.
If not there is a bus stop just outside the hotel and a regular service to Fuengirola where you can get transport to other places such as Malaga or Marbella if you so wish.
Its a good choice of holiday in my opinion.
