OK just to be different Iam going to suggest that an 'ideal' first turbine model in my opinion anyway should be one with an externally mounted turbine like the Kangaroo, Hotspot, Bobcat etc, etc. reason is the simplified engine access......
I will assume flying ability is not an issue either of coarse and that docile aircraft flying qualities are secondary to imediate engine access and servicability for a 'turbine trainer' and in the possible event of a hot start the external set up is an advantage.

Cheers-