For leather a wipe down with warm water and soap every week or two is ideal. If you don't want to do that, a synthetic spray cleaner is better than nothing. The main thing to do for leather preservation is to keep it clean.
When you buy the CX-9 I suggest waiting at least 6 weeks before making any modifications (such as interior wood delete). My guess is that after a few drives your wife become accustomed to the look, maybe even like it.
Buy a CX-5 GT, which has great handling and plenty of power for a vehicle of its size/weight. Really a well balanced , great driving compact SUV.
I've been driving a CX-5's for going on 5 years in a city with steep hills as well as very congested freeway's, not once have I desired "more power"...