As a wise man once said (Eddie?) ... "its all about the patina, baby!" ... and its all so true.
As my friends all know, I'm a huge T-dial fan and to me, its 99.999% about the dial. If its clean, outstanding and the watch is well maintained, I will forgive a lot of things ... missing bits and pieces, even whether the watch has been polished or not (if priced accordingly of course)
The next question would be, for the T dial, what is "outstanding" and after many years, I realised that its partly a matter of personal taste. I love flaming, yellow dials under natural light. I don't like dirty dials, but that's just me.
The A vs BT debate ... again, no straight answer. Usually I will adamently be for the A ... frankly I still have my doubts about the BT. But I have seen an outstanding 2 BT and the dial is so brilliant that I would probably have forgiven it as well! LOL
The markers on the 1A are clearly fatter than that on the 2A/ BT but again the answer is not straightforward. My 2A markers are actually a much more pleasing shade of deeper yellow, though being a bit thinner than my 1A.
And finally on the issue of Base vs side seconds .... and AGAIN (sorry!) it comes down to the quality of the T dial. I am generally a Base fan but am not dogmatic about it.
Sorry for such a long winded and confusing answer but this is a result of a few years of this T dial insanity
Best of luck in your purchase, you won't regret it! I took quite a bit of pain in clearing out my then pieces to got the T dial route but have had not regrets since!