Topoi has a series of “untimely reviews”, where classic works of philosophy are reviewed as if they had just been published. Hannes Leitgeb did one on Carnap’s Aufbau, where he not only pretends that it was just published, but also pretends (as I guess you’d have to if you take the premise seriously) that it wasn’t published 80 years ago (philosophy would have looked very different). I would write more and link to it, but I discovered that Chris Pincock blogged this already three months ago (and I missed it/forgot about it), so I’ll just send you over to his great blog. Also, read Chris’s Philosophy Compass paper on the Aufbau! And: Hannes’s serious, substantial, long-awaited paper “New life for Carnap’s Aufbau?” is out in Synthese online first (free preprint in the philsci archive). Here many of the things he hints at in the review are spelled out.