Eh, I'd get your commercial in power first, if you intend to do both. You can do the Commercial glider as an add-on to you CSEL, but not the other way around. As far as getting your CFIG as an inital CFI, any inital CFI ticket will have you being run through the wringer, but you might get run through twice if you do your CFIG first, followed by your CFI.
Getting you tailwheel and tow endorsements might be worthwhile, the tailwheel is a lot of fun and it will improving your flying. As far as towing, if its being done in a tailwheel aircraft expect them to require at least 25 hours of tailwheel time, plus your CSEL if your doing it for pay and probably a high power endorsement, before they will even consider it. Also consider that flying a tow plane is hot, tiring and can be a bit dangerous, the first guy I knew who died in an airplane died towing. Its a lot like being paid to do stop and gos.
Glider bumming can be a blast, and being a triple threat "fly, tow & instruct" will making getting a gig a lot easier, but unless you can get on at a big operation it will be at best a beer money gig.
One way to work you way into a job is to make yourself available to work on the ground, wing running, hookups ect. Then when they need someone to tow, fly a guest ride, do an intro lesson your johnny on the spot.
The biggest hurdle is that gliding is almost pure recreational flying. Many of the people involved are semi-retired or have day jobs that actually pay the bills, they are at the gliderport to get their flying jollies and make a few bucks. That being said, the very first flight I got paid to do was a glider flight, and I did it about an hour after my check ride. Good luck with it.