Sadly when it comes to porting over a lot of the existing Java BlockWars maps, a lot of them are horrible with Bedrock gameplay. They are either not Bedrock user friendly, or they need a lot of editing which isn't the best. With the 3 new maps we're going to add, myself & Younisco wanted BlockWars maps that aren't all like the existing Bedrock ones, completely flat and really small, there needs to be diversity and uniqueness to them.
I must note that if the Java community dislikes a map, it doesn't statistically mean Bedrock players will dislike it too, they are a different community and have different thoughts. With that being said, we're going to continue with the 3 current maps, but I'll look into tweaking the Mushroom map a bit. Every map won't be loved by every player, there will be favourites.
Keep in mind that I'm saying this from the perspective of someone who has played absurd amounts of both java and bedrock blockwars. We have a community discord server with almost every person on the leaderboard and people are very happy with the quality and variety of maps there currently are so I'm not sure that many java maps need to be ported to bedrock. The community and build team can easily make their own maps, so it can be a bright fresh experience for anyone trying each for the first time. I'm thinking of making more unique maps myself but obviously you dont want to just rely on me for it.
Another issue is that on bedrock, it is expected that blockwars is a fast pace game that ends in <1:30 nearly always and changing that for the sake of variety is changing the essence of it. People love fast paced games in every game mode; especially one that's already known for being quick.
On the issue of having maps that could be very disliked: bedrock doesnt have map selection, so if you keep running into a handful of bad maps, it can be very frustrating to leave and rejoin until you get one good after possibly 5 or more attempts. This is a bigger issue in this this than, for example: eggwars as those games take much longer so a small fraction of time is spent map hunting.
People like the consistency of the game, with every map taking within 10s of each other to complete optimally, there are no bogey maps, but each map has a different way to do it best, with different gear, layout and different places to do the best bridges. If its proven to be what people like, then I and many others think it should stay that way.
I don't know what you have in store but having long maps for the sake of long maps hurts the game and the community.