I want to modify my current bikes into some kind of a gravel - help with the right strategy

Hi everyone,

I'm, in a need o a bike. Mostly to keep up with my girlfriend on our road trips: mostly asphalt but occasionally we turn into dirt/gravel/forest roads... unfortunately this means that my road bike on narrow tires won't work. I want it to be very budget friendly, DYI and preferably to reuse what I currently have.

I have currently two bikes laying around:
- 2011 Specialized Crossroads Sport XL/28'
- 2005 Scott Yecora Disc M/26"

I'm 6'1" and 220lbs - Scott is too small for me. And Specialized although has a good size - it's more of an hybrid/trekking bike.

Route A - Building on my Specialized:
- I need to solve the relaxed position: I was thinking about getting a carbon fork, stealing my flat bar setup from my Scott
- But for a fork like that I need to convert to front disc brakes (which I'll get from my Scott). But then converting to drop bar handles is going to be tricky as I'm sure my discs are long pull. But this means buying a front wheel with disc brake mounts.
Although I could convert this to 1x7 - I could buy long pull drop bar handle and for the rear v-brake I would just align it tighter.

Route B - Building on my Scott
- First of all - I'm very surprised I was able to fit a 700c tire at the back of my Scott! That's why I'm even considering building on this frame. But the main problem I need to fix in this bike is the speed and the rolling resistance. I tried riding behind my girlfriend and to keep up I had to pedal like my life depends on it.
But this means I need to buy two wheels/tires
- Same as with Spec - carbon fork ... mostly to get some rigidity
- I would like to get a drop bar to fix the position a bit... but once again my brakes are long pull... and all my ideas are pretty pricey. And I'm not too excited about investing into frame too small :/

Any tips?