Speaking as someone who runs their own business (IT Consultancy)...
My advice would be to Not to use your student loan etc for learning to fly, Learning to fly is an expensive enough hobby that you dont really want to be paying any interest on top of. Likewise once you do have your PPL you will still be paying the loan off for the lessons and would have reduced spare cash available to persue flying on that licence and staying current. From what I have read there are few instructors jobs available at the moment so you would be placing all your eggs in one basket so to speak.
My advice would be only start your PPL if you have the income to support paying for the lessons and remaining current afterwards. You also have to factor the amount of groundschool time and the exams you have to part and whether they would interfere with your uni studies.
If your considering an MBA (Masters of Business Administration) then you may wish to consider going part time instead of full time - You can do this online with both the Open University and Liverpool University. I did my MSc with Liverpool and it is quite easy to fit around any work commitments as you pick your modules and when and set aside 8 week blocks. Doing it part time will allow you to continue working and also gives you gaps where by you can study for your PPL (whilst having the income to do so if working).
Finally there is alot of time spent involved in running a business, the paperwork involved can be quite large and there is the book keeping to do. If you find yourself a good accountant they will do most of this for you but they will charge - for example my consultancy is a Limited company and pays about £1200 in accountancy fee's even tho I do my own invoicing and VAT returns. You have to factor in the administration time for your company along with any working time - for example I work 5 days a week consulting and do my bookwork on a sunday afternoon.