I believe the Order, as it is, is pretty strong; the only alternative is that I'm getting much better at this game, and isn't supported by other games I played recently
Compared to Ulm, the Order has access to strong priests, and that IMHO makes a big difference - Ulm has trouble using Sermon of Courage, while an Order of Light army can be accompanied by a level 4 priest for Fanaticism (and two cheap [indie] Astral mages will make the same Smite-capable with a Communion).
The OoL Infantry is comparable to the regular Ulm infantry (not Black Plate): slightly higher resource cost, better stats overall. The gold cost is higher, but the gold cost will never be the limiting factor, unless you're buying lots of mages. The OoL infantry are slightly slower on the battlefield (except compared to some of the 1/5 Black Plate), except the Standard Bearers (who tend to run
before the rest of the squad and get slaughtered by the enemy's front line - are they given the standard because they're too stupid to wield normal weapons?
).
The Knights are almost identical to Ulm's Black Knights (1 less HP, 1 less Prot, 2 more MR, 4 more Def, Broadsword instead of Morningstar), but then the Order has the option of the cheaper Horsemen,
and the Chariot, which is a fast trampler with good morale (especially with a few surviving standard bearers and availability of high-level priests) and excellent protection.
Overall, I believe the Order has the upper hand on basic Ulm; not having the access to the Forging bonus is more than made up for by the better access to priests, and the higher gold cost of the infantry isn't really relevant.
Still, they're a very enjoyable nation to play