This can be a general feedback thread I don't mind!
I fully agree that United Earth's units are super good, most of their pieces are so powerful they work in almost all situations. Battleships are extremely versatile, given enough time any of the weaker ships can become one as well, and the the Artillery have some of the best area denial on the board.
As for Tokinko, I don't play them much, but my friend chooses them a lot when we play together. I've definitely noticed a lack of "offensive speed" with Tokinko. I'm the type to choose weirder characters like Metonym and Soft Swarm, and I find I'm always "leading" the battle, making the offensive moves and forcing her to react, almost never the other way around. I wouldn't know how to change this, as Shogi is inherently a slower and more tactical game with much of a pieces movement blocked due to "the drop rule." Relic choice can go a ways to mitigate this, but I haven't messed around with the relics fully enough to really grasp their usefulness to the best potential.