I honestly have no problem with having all three types of dropship. As for a nose turret in the base transport, I wouldn't add one but would include the module type I spoke of in my own post of several months ago (
https://forums.dust514.com/default.aspx?g=posts&m=935374#post935374) that allows the side turrets to be fixed forward (barring a module, I could see them as alternate turret types that you specialized in like the various infantry weapon specializations).
I could see the transport truly living up to it's name by including an in-built RDV like tractor module and vastly superior torque that would allow it to move any manner of battlefield item to new and better locations. Don't need that resupply depot half a click behind the lines? Pick it up and move it where you want it. The Logi can't do it because the built in CRU drains power from available torque and the Assault spends its PG on acceleration. This could be balanced by having installations so moved be unusable until a certain period of time had passed and by having terrain requirements be met before activation could occur (not drop off mind you, just activation).
Removing the side turrets from the Logi while adding a nose gun would force blueberries spawning in to actually get out instead of clipping you with your own weapons while firing on allies and keeping you able to at least make a potshot or two in between dropoffs into hot zones
Finally, I have no objections to removing some seats from the assault so long as this corresponds with an increase in available ammo for the turrets (once ammo is implemented).
I think a good analogy of most peoples view of the dropships is:
Transport = American Huey, Logistics = American Blackhawk, and Assault = Russian Hind.
But I don't think we've actually come that far in the design stage. Instead, I think a better analogy is to look at the current lineup of DS as variants of a single type: The Bell UH-1 Iroquois or 'Huey'
Transport = UH-1H edit:(basic transport)
Logistics = UH-1P edit:(special ops and attack ops use)
Assault = UH-1M edit:(gunship)
Keeping this analogy in mind, I hope you can see where my line of reasoning is going. I think the differentiation between Dropships should focus more on differing stat bonuses combined with differing racial bonuses and less on making each DS its own beast. I think we need to nail down the interrelationship between racial variants and role variants before we start throwing in truly different models of Dropship that will increase that complexity by a wide margin, a complexity I only welcome if it doesn't break my Dropships or the game.