@mattbarnes I haven't seen Saruman take Tharbad, usually they need everything they have vs Rohan. I'm curious how this strategy has worked out for you or your opponent.
I've seen Goblins take Tharbad early and then fortify it (freefolk don't have siege so they can hold ok) however this means less pressure on lorien and high elves. It put goblins into a long-term defensive position but that was ok.
I've seen freefolk mostly go all-in on south (crossing at Tharbad and flooding goblins/saruman), or north to help contain Angmar and then flood over to the other side of the misty mountains. Going south seemed to work better tbh, but if for some reason wood elves or the northmen are doing poorly sending some units across can help counter.
I've not seen a Gondor/Harad naval arms race though I'm sure it could happen. Harad doesn't really have the income for more than a turn or two of ship production anyways if they want to remain a land threat. It's more that Harad can go full land and work with Mordor for an osgiliath crossing or a fords crossing, while using what ships they have to distract gondor units. Or, spend a bit on ships for a turn or two, then gondor has to pick what they want to defend by sea, then harad can land elsewhere. Gondor's sea front is just too large for them to effectively defend by sea. But really the most effective non-lore strat for gondor has been just to send some of their starting units through dunharrow to help rohan.