Never had an Acrobat player, even when the DnD cartoon was still new and the class was appearing in Dragon.As someone who started with 1E, I have a hard time imagining someone pining to play an acrobat instead of a B/X class.
You can always buy the Advanced Set, and then not use all of the Advanced material. I mean, there are a lot of options that are offered, between classes, weapon specialization, how spells are handled, class as race (or not), extra weapons and equipment (and all these expanded a lot in the Carcass Crawler Zines, which I rather like).
One thing I'm wrestling with is limiting what classes are on offer for a particular campaign. I think Necrotic Gnome assumes the following (from Carcass Crawler 2):
Too Many Options?
The new classes and races in this article are entirely optional. Some groups love a wide selection of character types, relishing the variety that offers. Other groups prefer a more limited number of options. As always: do what makes your games most enjoyable for your group.
One approach that works well is for the referee to select a limited set of around 7–10 classes / races that suit the flavour of the campaign. For example, in one campaign, wood elves may replace standard elves.
In this way, the number of options available to players when creating characters is kept within reasonable bounds, while the hand-picked set of allowed classes and races can heavily reinforce the flavour of the specific campaign.