Looking less like a boarding craft and more of an APC? So.....unless there is a hangar bay to land in I guess it will drop troops on the hull and say... good luck getting in the ship?
Back when RSI announced the Cutlass would not get a docking collar, it became evident they are not going to plan a huge advantage for them in ship boarding. So long as personal armor can be used as a vacuum suit, boarders probably are better off breaching hulls in multiple places rather than attacking through the expected airlock. So in effect what you say is true. There becomes little difference between a dedicated boarding craft and a troop transport so far as doors are concerned.
RSI has however suggested that the Prowler is unusually sneaky. It will supposedly be a stealth ship. If it performs as hoped, it will be much more than an APC. If you can use this to sneak up on a Polaris, Void Bomber, or Idris, it will be worth every penny of the $425. With 2-3 of these a committed team could make it their mission to steal very expensive ships on a regular basis. What would any self-respecting pirate or privateer not pay for that?
Compare it to a Retaliator transport or a pair of Redeemers, or a pair of Hoplites. In all cases this requires less crew. The Prowler will be slower than all these others save perhaps the Retaliator. 4XS4 + 1XS6 guns could be good firepower for just two gunners, including the pilot.
No missiles. For boarding you want to have missiles to spike with and we've been told several times that boarding is really a team effort requiring several ships. So what do you want to team this with that optimizes missile load-out, could be made stealthy, and is not especially fast? Looks like a reason to build a few Ghost Gladiators to me. If you can remove the turret from the Gladiator and put in the Hornet Tracker turret or the Warlock's EMP Generator, all the better.
We seldom talk about the Gladiators, but here is where they might shine. A single Gladiator can carry 12 Arrester III missiles that do 1,200 distortion damage each, lock at 12 km and can range out to 36 km. And then there are the 4 Stalker V's they can carry that do even more damage and lock/track targets from 20 km. If you had an NPC flying a Ghost Gladiator as escort, there are lots of ships just two players on the Prowler might be able to manage.
Count me intrigued. If you could lock cargo to the floor for multi-purpose I'd be far more enthused, and if we knew a single player could control 14 NPC marines that would be a selling point. I do love the speed and versatility of the Vanguards, so I will need some convincing the Prowler is a better choice for privateering, but so far it looks good, and it is cheaper than the pair of Hoplites it replaces.