Welcome to the Site mate,
Personally whilst I admire your ambition I think that it is maybe a little too ambitious. The smaller engine would probably react well in terms of power gain but to get it to that stage you would be talking a massive price for the power. Think turbo unit, Intercooler, hoses, remap, fitting, new intake etc.
Put simply I would start with a turbo car and then start thinking of hybrid turbos and uprated turbo units rather than starting on a naturally aspirated engine.
If you do go for the naturally aspirated option and go ahead with the turbo I would firstly speak to your bank manager. After he has agreed the re-mortgage on your house then give turbo-technics (in northampton) a call and see what they would recommend. They do servicing and hybrid conversions along with superchargers and replacement units and have been about for a while so should be able to give you sound advice.
Let us know how you get on as it would be interesting to see the results and good luck whatever option you choose.