Hit the Diamond was a lot of fun, but sometimes episodes with a lot of fun also use the shenanigans on screen as a path to show us more about the world that Steven inhabits. This was definitely one of those episodes, actually showing us one thing that really challenges how the earlier homeworld was portrayed.
Man, Rubies are dumb
Rubies may not be the wisest Gems in the homeworld’s armies (at least we hope they aren’t), but the quirky Ruby squad we saw in Hit the Diamond was nothing like the trio of Rubies we saw in The Answer; each was incredibly distinct in personality, making them instantly recognizable as very much not alike.
In The Answer our Ruby was obviously calmer and more reasonable than the other two, but all three seemed like rough-and-tumble little scrappers and all acted identically toward Sapphire and when the battle started. To drive home their similarity further their outfits were also identical.
Contrast to the squad of Rubies sent to search for Jasper: distinct outfits, and radically different personalities—aside from their desire to do their job there wasn’t a whole lot alike about this batch. This definitely isn’t what we’d expect to see if Rubies were all based on the same mental pattern, or even if they were all a blank slate taught to act alike.
With so much individualism on display, we don’t know what to think. Perhaps the homeworld has always had such differences between individual Gems of the same type and The Answer just gave us the wrong idea. Perhaps things have loosened up on the homeworld, or maybe Jasper isn’t as important as she might like to think she is and they sent the defective Rubies to find her (it’s interesting to note that the Rubies only appeared after the Cluster would have emerged—realistically the homeworld wouldn’t know Earth should have been destroyed by then, but with such little time they sent an obviously incompetent team).
A cheap, but effective, tactic
Five angry Rubies fused into one huge angry Ruby are quite intimidating. Standing at least as tall as Opal and much bulkier, they may very well have been able to beat the Crystal Gems had Peridot and Steven not defused the situation (no pun intended).
Despite Jasper’s protestations that this force multiplier (imagine the same fight but with the Rubies staying separated—it would still a challenge but feels much easier for the Crystal Gems, right?) is a tactic of the weak, we do know that quartzes fighting on the side of the homeworld used it during the war. We saw lots of quartzes not using it, however, even in a battle they were losing; the Rubies sent to escort Sapphire, however, were always meant to fuse in the event of a fight.
This leaves strong soldiers being quite valued for their ability to fight individually if needed, while still being able to form still more powerful combatants if needed. Weak soldiers, the Rubies, still haven’t been portrayed even trying to fight without fusing, always being sent at the enemy in packs. Just like when she chose to fuse with Lapis to try to beat Garnet, Jasper still gets to have her smug sense of superiority (she was willing to fight one against two, after all, because she’s just that strong) but fuse too if the situation calls for it.
It looks like we’ve finally got to see what the Gems use to travel the universe instead of “primitive propulsion-based space travel”. Whatever it is, it can produce some very fast acceleration. More importantly, even a small scout craft has been shown to carry this technology. With no lower size limit shown, the plug robonoids from Marble Madness could even have been traveling to Earth under their own power. The hand ship that Peridot and Jasper arrived in would certainly have been large enough if the roaming eye was, and made the same sound when it arrived at Earth (though obviously much louder, generating powerful enough sonic waves to damage Beach City).