I've been carrying a PM 9 in my $15 belly band for the last 5 years of my 17 years of CCW. I experienced all the same issues as you trying to conceal in work clothes with standard holster and could only pull it off by adding a Columbia Sportsear Vest to the outfit which looked a bit obvious in summer months.
These belly bands are the best kept secret of experienced EDC people and come with the added benefit of not needing to unholster if mother nature calls for a class 2 download!
Just tug the whole rig up a bit and take care of business without needing to balance a gun on a TP holder...
My only concern with your set up would be doing this with a single action pistol. My band does not have any rigid barrier covering the trigger area so I would be worried about the possibility of the safety being bumped off and a foreign object...like a seatbelt...acting on the trigger through thin slacks and elastic.
If your going to carry an SA pistol in this fashion I would suggest stitching a leather paddle to the outboard side of the gun compartment on the BB just to bs safe.
My Kahr has a long, smooth, DA only trigger so it's not really a concern with this gun.
Also, I finally got to shoot a solo Sunday before last and liked the gun but I will say it was more difficult to hold on to than my PM 9 due to the smooth metal frontstrap. If I ever do buy a solo, I would opt for either front strap checkering OR simply cut and apply some skate board tape to give it more grip.
Good luck and I glad you finally tried the perfect system for those of us who must dress in office work attire.