comes in handy a lot, but you can survive without it. impact driver like electric are super fun. the hammer ones work too.
hardly think a torque wrench is essential. you can get by without one if you're not hulking things.
I use a limited set. skip all sizes under 8, never need a 9. a long 11 is important for tomos, and long 10 is nice to have.
10 for everything, 11 for tomos moby other oddballs with m7s. 12/13 for general fasteing mount bolts etc, 14, 15 17 for big bolts and axles etc.
16 and 18 (long both) only if you've got motorcycles with other size spark plus. 19, 20 generally useless, 21 is some axles. and a spark plug obv.
T-handle hex-key set
meh, 4,5,6 allen is all I keep, sometimes an 8 if I've got big allen m12 bolts
Piston stop A+
Tire Levers (large metal ones) key. 2 levers. fuck a third.
Screw-Driver set, yes. at least 2 each, big and tiny. and maybe micro flat for wiring blocks.
Adjustable Wrench yeah.
Vise & Clamps (for holding things)
usually get away without it.
Air Pump (obviously)
Pressure Testerdang. nah. never had, never needed. you can easily tell if you've got a compression issue. maybe useful for getting to 100% perfect status, but 99% is doable without.
Empty Squeeze Bottle true, handy. or I just get a little cone cap that screws onto whatever bottle. gear oil comes with these caps and I just save the cap after.
for other suggestions, you can totally find TDC just fine with a screwdriver and diligence.
angle grinder and mallet are good calls.
I'd be fucked often without a drill.
also a flywheel puller. its not essential but I use it as much as some other tools. so much it's in my togo rally toolkit. youd be surprised how many people borrow it too. (puch derbi tomos sachs bosch threaded...)
a small pointy set of pliers can do a lot on the fly, pick dropped shit outta small holes or start difficult nuts in hard to reach places, or if you're good - tackle circlips too.
a sharpie comes in crazy handy very often. a knife also - especially w wiring.
always always carry zipties. perfect quickfix. hell we've even replaced busted spark plug boots with clever ziptieing.
these are all in my togo kit. can do most anything and it weighs at like 2lb.