In terms of comfort in locally available options I'd rank
- GD110 (A friend has it)
- YBR Z
- Pridor
- YBR G (I own one)
Derbi was also good but it isn't that pocket friendly, I think you should go for YBR Z variant as you'll be covering long routes.
GD110's maintenance from dealership is expensive and the schedule calls for an oil change every 1000km
On YBR the manual calls for oil change every 3000km I haven't tested it that far but I have stretched it to 2000km without any issues. The oil that comes out seems like it has done it's job properly and still maintaining lubricity.
I have also ridden CD70 and CG125 extensively as both are our national bikes 
I have no experience with GS150 so I can't comment on that.
Why I ranked YBR G lower? The seat foam on my YBR G went so bad in a few months of use (around 6k km) that there was an impression of my buttocks imprinted on it, I got it replaced in warranty but same situation after a few months. I have observed that earlier YBR and YBR G that came with perforated type seat covers didn't suffer this issue. And I feel while it absorbs speed breakers better (i e. Going above speed breakers at speed without turning your insides out)
Pridor kinda beats it when going on repeated bumps (e.g. under construction roads) at medium speed.
