I've gone with carrier-sleds occasionally. The carriers need naval shipyards. The tractors need a few layers of armor, CISW, and AMM escorts (which are there for the carrier, anyway.)
Do you feel that this is a significant saving over bringing along giant tankers and additional fuel harvester infrastructure to support them? The tankers, at least, are civilian vessels. That's what I've used for my 1.5x power engines in my current beam-heavy game - one tanker per two cruiser-sized ships. I use forward scouts launched from boat bays and thus haven't lost a tanker as of yet. I do, however, wind up with rather a lot of fuel harvesters.