I really like the style of holster like the IWB-P1 that JRC Holsters does, for something that isn't super heavy like a 1911. The hybrid model that JMCK and JRC collaborate on looks like it could be an option to consider as well.
I definitely suggest getting a full sized P30 holster, as it will also accommodate your VP9!
I also third the suggestion of suspenders, at least as a stop-gap until you have hit your fitness goal.