Those using the slippery slope argument in regards to Frontier offering early access for new ships and the jump start packages are engaging in a logical fallacy. I'm not saying it couldn't become a slippery slope but the fallacious aspect is that it doesn't have to follow as a logical step at all, and presenting it so is misleading at best.
Also, the jumpstart packages being pay to win is just plain wrong at this point. However, I would say that offering a Fleet Carrier for Arx would qualify as pay to win, but even if they did that, how much Arx would it cost to justify the most massive and expensive end game ship in the game? $20-40 ain't cutting it. I'd say it would be approaching Star Citizen levels of price with a Fleet Carrier being priced around $500-$1000 to justify what you're getting, and if they skip the upkeep, then I'd definitely say go higher than that.
I think it would be a very bad move to offer a Fleet Carrier for Arx, and IMO Frontier shouldn't entertain the idea at all. However, some more carrier layouts and other cosmetics would actually be very welcome at this point, and I think would more than suffice to be a nice purchasable item for those who wish to support Frontier and get something cool whilst doing so.
TL

R - Fleet Carrier for Arx? Absolutely not.