Alright, so let's move down through the list of things we have:
- Feats of ridiculous strength (house towing prana)
I'm not sure that's a unique feature of earth ponies, or if it was just because Big Mac has a STR 10 and Large Frame (And probably Strong Back, the perk that gives you +50 to your carrying capacity). Combine that with the effects of the 'love poison' (which I imagine enhanced his abilities so long as he was going to get to his schnooky-wookums) and that is a good explanation.
Maybe a perk that let's them double or triple their carrying capacity for the purposes of dragging? Though, I'm actually surprised we don't have rules for the amount of weight a pony can drag. - Mass earth movements (minecraft method)
Solo, or with Raise this Barn? - Temporary aviation (jetpacks)
Ok, we need to answer how temporary and what rank of flight it gives. Flight 2 would put it squarely in the level 14 area (possibly lowered by one or two levels if it had an extremely short duration) as that is the level that a Unicorn can learn the Wings spell and gain flight 2. Flight 1 would be simpler, available at level 8 and could work similarly to a Bloodwing Talisman. - Concept space for vehicles of various kinds
Oooh, you don't think small, do you? Ok, so let's outline what type of vehicles we should be looking at. I can use my experience with the Stalliongrad game, my work as an engineer (RL) and my experience as a farmer (RL) to give us a rough materials list.
Tractor (Ground, possibly air)
Motorized Wagon (Ground)
Flying Wagon (Air, possibly in the same vein as Chitty Chitty Bang Bang).
Airship (Zeppelin!)
Mole Machine (Burrowing Underground)
Any other ideas on vehicles?