Hi Paul. There's not a lot you can do to the engine easily, due to access and complexity. Servicing is probably best left to a dealer, it's wings and cowl off to change plugs and air filter. So a bit fiddly to do much yourself other than a fluids and visual check.
A battery conditioner is a must, as they seem to drain down the battery within a few days.
Quite a few Aero owners have added their own twists to their interiors, ICE, speakers. Though many of us feel the side pipes supply the best soundtrack!
Allon Whites do nifty headrest pads that slip over the headrest, but from personal experience they tend to fly off and out when "pushing on" get them to add a flap to drop behind the seatbelt arm to hold them on.
The windscreen wipers are useless (it's the same on all Mogs) and take care adjusting / tightening the wing mirrors. The quarter light glass breaks easily and I believe they are rarer than a flying pig nowdays.
Most of all get out there and enjoy it.
