Speed is the big problem with the pelta battle wagon, carriers can get away with a bit slow as your fighter wing does the moving and reaching out and you can try and keep away from trouble.

A battle wagon ( especially with back dice and ordinance ) needs to get in fast: to have the threat range that restricts your oppositions options and be sticking damage in the right rounds ( early damage is better that late damage as dead ships don’t fight back). A slow battle wagon can be avoided or worked so that it gets to the engagement when the other player wants it.

The other big problem is no small based ships can tank over time, they need speed to get out a problem. A speed two large base ship can sit there and take the pounding,a speed two small base is just prey that can’t escape . If I had the choice of a small base battle wagon it would always be a CR90 or mc 30 for Rebs and corvette or glad for imps all these ships work because of their speed, which gives them threat range, the freedom to engage early or when they want to and the ability to run at high speed even from bomber balls.

I did try using a pelta in the battle ship role for an MSU, it just did not get where it was needed in good time to make much difference.