I'm rather a fan of hollow-body guitars, but the Gretsch range has never really appealed to me. I can't speak for any modern, current, models, but 'back then' ('70s...), the ones I came across didn't inspire me much at all, with a rather limited tonal range, electrified, and not much tone at all as an acoustic. I found them to be extraordinarily heavy and clumsy, too, compared to other arch-tops or acoustic guitars. I suppose if one just has to have that particular sound, they don't have much competition, I certainly won't be scouring the small ads to find one. What is it that draws you to them, and what models are your present guitars that you're willing to sacrifice..?
At the risk (nay, certainty...) of sounding like an old frump, I'm not a fan of tremolos on any guitar, and definitely not the Bigsby version. Heavy, clumsy, detrimental to the tone and robustness of any arch-top guitar sound-board, it's a deal-breaker for me. Do they mess much with tuning..? They certainly don't if they're not fitted..! Again, it's a matter of what one wants to play, and I've never wanted to play in any style that uses such an effect, soooooo... Not for me, thanks.