DC did that to with other characters than Bumble Bee, apparently that strategy didn't work out for them. And they don't have something as big as the MCU that might get casual fans to pick up trades for these characters.
DC strategy seems at the moment more to be to double down on quality and popular characters and creators.
There is at least not much of reason to giver her a trade, instead of DCS other C or D-Listers (of which they they have plenty). And what chance does she have, when even way more popular Titans (Raven, Starfire, Cyborg) can't keep books going.
With a good idea you can make such a character a success, but for the most part it doesn't work out.
Even if I go by your examples, are not particularly successful when it comes to comic sales on the direct market.
- Rockets longest lasting series has lastet for 11 issues
- The Attempt for a Static Series when the New 52 was launched flopped
- Squirrel Girls sales on the direct market are at best around 10K copies per issue