I'd have a serious look at the new diesel Robin DR400:
Low fuel costs (~£7/hr)
Robust engine, water cooled doesn't mind PFLs circuits etc.
2+2 configuration, so difficult to overload 2-up
Good handling and visibility
Against:
Cost of new plane over £100k
Needs hangarage
Overhaul at 1000hrs (will probably increase)
Not spin approved
If you can get 500hrs a year over 10 years I think the financial bit would be favourable