There are only three things I would do different.
- is under car exhaust. It is stunning how loud the side pipes are and seem to get louder as we age.
- I think just as important, is EFI with traction control, a flex fuel capability and a mature Mass Air Flow fueling model. I put it on after the fact because I couldn't find what I wanted technology-wise or feature-wise at the time. DIY Automotive solved the problem when they productized the longstanding MegaSquirt Heathkit style EFI into a factory built product with a lifetime warranty. The system I ended up with was their MS3Pro Plug and Play system for an 03/04 SVT Cobra that used all the factory sensors and factory wiring harness with expansion capabilities way in excess of anything I will ever use. Very price competitive too $1349 with everything including tuning software, data logging software, a base tune that gets the car up and running instantly and some neat extra's like wireless Bluetooth communications with error detection and correction.
- is power steering. I know wimp / wimp / wimp. I am still finalizing my research but I will almost certainly use an electric power steering solution for simplicity and space considerations.
If you base the importance to me on the number of words I choose to describe them, EFI is clearly #1, power steering is #2 and under car exhaust is #3. In my real world they are so closely grouped it is difficult to set hard and fast rankings or priorities.
Ed
p.s. In the nice to have category is a removable steering wheel. If you haven't seen Patrick's, you need to look at a few of his posts about the ERA solution he has. To say it is 'to die for', is an understatement. It is easily the most elegant and invisible solution I have ever seen!