As much as I loved the A-tab in every other MMO I played, I believe that what is needed here is improve the curent system that allows for visual customization. Mesh wise, and I repeat, MESH wise (for those who don't know tech speak is the shape of the model) there is really a low variety when it comes to crafted gear. I have armortech on one of my toons and from level 11 to 50 gear I only have 3 different meshes available for crafting (blueprints from the trainer). The only thing that differs is the color pattern. Which is what makes the difference on a good 75 to 80% of the gear ingame. And is something I really believe needs improvement from the Devs.
Coming to moddable gear. It's true, it requires some work to get what you want and sometimes it can be a guessgame, but I believe in general works. What doesn't work, is the fact that color patterns are locked and do not mix up together on a good 60% of cases, lowering the appearance customizability a lot. If I want to create a certain look, I shouldn't be forced to wear what the Devs created as a set, to have a nice looking set. I've tried mix-matching stuff between crafted stuff, some loot and PvP armors (Yeah it was a pain running around all the time with the dressing room up on screen to not loose the apperances) and what I found out is that as much as with mesh models things would lok good together, most of the time color patterns were completely off and few times slightly asimmetrical but still decent, going down to really very few mixes that were really good looking overall. That is something I believe can be easily solved by implementing a colour costumization system, and since it's something BW is working on "in some form" we only will need to wait.
And on the long argument of "you peeps just want everything handed to you from the start" against "I don't want everything at the start, I want something simple" I just want to remember everyone this: on SWG (since it's being called for comparison many times) post-NGE you werent able to wear armor until lvl22, but then apart from some armor that was level or class restricted because of the stats or game design decisions (like the Boba Fett style Mando armor for the latter), from lvl22 on you could wear any mesh variation of armor your class allowed you to from that level until cap. The great thing was, you could mix and match as you pleased because there were armor coloring kits (crafted, so making crafters needed and a plus source of income for them) allowing you to look cool whenever.
other MMOs don't do that and keep the armor mesh variations hard-linked into lvl ranges, so you would still need to level up to wear a specific appearance (meaning waiting to look exactly as you wanted to) but on the road to that, since you can dye the armor as you want to you can still look good and not like you dressed up hastily in the morning with the lights off without looking. Which is something lacking in TOR. Doing any possible colour variation for items is a really daunting task for the devs, not to mention it requires an absurd amount of resource files put into the game because each variation would need to be a standalone item. With a dye system one has the same result, if not better, since the files are a lot fewer and the players have almost complete control on the look.
So to make a long story short: an A-Tab would be cool, but improving on the currernt moddable system by combining it with a type of dye system would make visual customization a lot more interesting and enjoyable for everyone (yes, even those who claim they don't care).
Sorry for the wall of text, but I love SW, I love this game, and am an Hardcore RPer, so character customization is something I keep to my heart.