Just as FSOBass mentioned about adding handles, there are several other options if you really love your TNT. Not sure if your TNT115 has casters or not, but one option to look into would be a dolly for the amp, which also has a tilt-back function: http://www.handicart.com/carts.html#
Up until very recently, I had the TNT130 combo as well as the Peavey ProBass 500 / TVX210 / BX115-BW rig. Both were extremely awkward to haul around, but reliable, useful and ballsy amps.
I decided to sell them both and go lightweight, but I wanted whatever I ended up with to have some balls. I tested quite few micros, a few neos, and there are some great options out there. Mesa Walkabout and the Genz-Benz Shuttle are great. Lightweight, compact, and both companies have great cabinets to choose from, or you can choose your favorite cab or cab combinations. I also like the GK MB series combos...
Truthfully, other than the mini's, there wasn't anything that I hated.
After narrowing it down to TC Electronics RH450 and Markbass, I ended up with the Markbass CMD102P (210) combo and the 210 ext. cab. Real light, well built and plenty of volume.
Good luck with your decision.