Hi there here are some possible answers to your questions
1. insurance you would be advised to notify them (especially engine mods)
2. If you intend to comply to SVA what's the problem
3. If you comply you should not need quick fixes but if you do then you are only complying with the wishes of the inspector. re,emissions after the SVA at the present moment in time for MOT are visual only
4. you would need to notify DVLC of any changes to your engine regarding capacity or change of engine number
5. If you fit a hood then the hood studs that are now available should be SVA compliant
6. If you took a standard car with an after market exhaust(no radius)it would fail.
7. the SVA proves that the vehicle in question has been inspected and if passed is issued with an MAC cert,which is required to licence the vehicle from then on it is down to MOT
cheers
Paul