I experimented with the TC liquid trains a while ago. They can hold up to 100 buckets of liquid, much more than RC carts. Therefore a much more efficient system could be made with them.
However, the liquid trains don't work at all with liquid loaders/unloaders. But there is a fix: they can interact with item loaders. Use an item loader to load filled buckets into the train just as you would to a RC storage cart. Despite its appearance the TC train can fit under an item loader directly on top of a track. When a full bucket is loaded in the train, it will store the liquid and spit the empty bucket out. Use transposers, item clearers, or obsidian pipes to catch the bucket and return it to be filled and loaded again. For best performance obviously use multiple buckets. When the train is full of liquid, it will not accept buckets anymore, which will trigger the loader's redstone signal, and send the train off (if you use a boarding track).
Unloading is similar: use another item loader to load empty buckets into the train. The train will fill them up and spit out full buckets. Catch them with automation, empty them and load again until the train is empty.
Here comes the hard part: using a loader + boarding track on the unloading side won't work. If a full liquid train arrives to such a setup, the loader will think it's already full, and emit a redstone signal which will send the train off before it started unloading. You might need to use some kind of a piston launcher, or put the loader one block away from the boarding track - it can still reach the train. There is also no really simple method to detect when the train is empty. I tried item unloaders, but they don't really cooperate. You might have to result to some method of counting how many buckets you've filled - RP counters, CC computers, etc.
Last notes:
- If you are looking at the train's inventory while it is being loaded with buckets (empty or full), it will start spawning phantom buckets all around it. You can't pick them up, the only way you can get rid of them is by relogging.
- You can link TC trains with RC or SC carts (e.g. an anchor cart) using a RC crowbar.
- Unfortunately the TC liquid train can only hold water or lava, no Forge liquids.
All of this has been tested on MindCrack v7, some things might have changed in v8, take this with a grain of salt if you're using the latest version.