Hi
Correct me if I'm wrong, but it looks like that is a quilters cotton style fabric. Same fabric your sheets are made from. If so, I'm not surprised it's pretty diggy. Tbh no matter how well you break it in, that style won't be comfy with a larger baby.
If price is an issue, I would grab a Lenny lamb, or little frog. You can get wraps for under £50, sometimes much less if they are grade b's. They are 'proper' wovens and would be much much comfier.
Your other option would be to hire a wrap from your local sling library to play with.
Awesome wrapping btw