What cross pattern you can lace in is determined by the rim diameter vs the hub flange diameter, and whether or not the rim has angled spoke holes to match the lacing pattern you want to do.
The bigger the hub flanges, and the smaller the rim, the less crossings you can do.
The main reason people report breakage of 12g is because they are too thick to tension sufficiently on typical hubmotor bicycle rims, without causing the rims themselves to crack and fail even without road-strain.
11g are even thicker, and would exacerbate that problem, unless you also use a rim that's designed for at least that size spoke, so the spokes can be tensioned sufficiently to pre-stretch them and keep them tight under rim loading.
Thinner spokes (or double- or triple- butted, with thick ends but a thin middle to allow sufficient tensioning) solve the problems of wheels coming apart / spokes breaking due to the problems above.
With potholey roads, and heavy loads/bikes, rims have to be strong enough to not deform too much when there is a hit, but tires have to be big enough and have enough air in them to spread the hit around the whole rim so it doens't end up impacting the rim. Otherwise the rim gets deformed and all teh spokes are then loose, and then stuff starts breaking that didn't break because of the hit itself. If the hit is bad enough it can cause the rim to cut into/thru the tire/tube, and/or to deform and to suddenly overstretch spokes and potentially snap them.
However, it takes quite a bit to do the spoke snapping. I recently nicked the edge of a deep sharp pothole (deeper than my outstreched hand from pinky to thumb) where asphalt was completely missing at a bus stop, and the edge collapsed under my right rear wheel and sucked me into the pothole, slowing me from almsot 20MPH to nearly 10MPH in an instant, and taking all that inertia into the impact spot on the rim.
20" 45mm wide doublewall aluminum rim, 70-something mm long radially laced 13g non-butted Sapim spokes from Grin http://ebikes.ca into an HSR3548 DD hubmotor, Shinko 2.5" wide 16" moped/mc tire. SB Cruiser trike is a few hundred pounds, probably nearing 500lbs with my 180lbs weight riding it, and most of that weight is in teh back, and with the ~40lb battery and ~8lb charger and ~10lb toolbag just in front of that right rear wheel.
No spokes broke. One head pulled thru it's washer most of the way thru the oversized spoke holes on the hubmotor, and a few others pulled thru their washers there but didn't pull thru the oversized holes, and a few of the nipples partially stripped threads.
The rim itself had it's bead seat flange bent inward almost all the way down to the inner surface on teh impact point on the outboard side (no damage on the inboard side), and teh whole thing warped from the side loading during impact. It's bad enough that it's now untruable, but it's not unrideable. I rode the rest of the way to work and then my ride home later with that, and though I could feel the looseness of the wheel, nothing else broke on the ~3.5-4 miles, without changing my riding style (which is probably pretty hard on the wheels even normally
).
Later I re-rounded the rim via spoke tension/truing, after replacing the now-missing washers and the stripped spoke nipples, though I can't fix the side-to-side wobble. At some point I'll have to replace that rim.
Oh, and the same set of 13g spokes/motor/etc already survived a similar but not as bad hit on the previous (identical) rim.
I suspect but haven't tested that 14/15 butted spokes might have saved the most recent rim from all but the bead seat flange damage, as they would have been able to stretch more in impact, but having them longer (non-radial lacing) would have helped even more. (just not possible with the rim/hub I have to work with).
So you don't have to have thick spokes to have a wheel that can survive potholes under heavy loads.
You might have to have better *rims*, though.
If I ever run across some wide steel moped or motorcycle rims that will fit my Shinko tires, I'd give them a try (partly just because I can bend teh steel rim bead seat flange back in shape without cracking it, unlike the aluminum ones I have now, and partly because many of these wheels have angled nipple holes that would allow me to use longer spokes in at least a 1x pattern, which would let me have even more "suspension" in teh spokes that would help save teh rim in an impact like the ones that have so far destroyed two rims).
I have yet to find any steel rims that are anything other than single-wall, at least in the sizes I've looked at for the trike.
The bigger (larger diameter) the wheel is, the better it will ride over these holes, though, and the bigger (fatter) the tire is, the better, too. You may not be able to use a larger wheel on yours, but if you can, try that. Eventually I'll be rebuilding the back end of the SB Cruiser (or building a whole new one) to use at least 26" wheels back there, for those reasons, as the ~22" outer diameter I have now (16" Shinkos on 20" bike rims) gives a fairly harsh ride vs a comparable tire fatness on a 26" wheel.