LP's... Do they sound better now than 30 yrs ago?

Good recorded vintage LPs sounds amazing, it depends on the pressing quality and your equipment. Thickness of records means nothing to me, some of the 180g reissues remastered NOT from the original tapes, but from digital source, often overcompressed, and not suppass the good old original pressing. There are exceptions of course. In other words there is nothing wrong with the old records and nothing to surpass, really. Those fancy audiophile pressings are very expensive for modern LPs, you can not buy everything on virgin vinyl pressed in Japan. You’d better think about the cartridge/turntable and the whole system instead. 

Chakster is bang on

It’s still going to be a lot of effort but since you were last around record cleaning has come a long way. Ultrasonic in particular is a major step forward so if you do get back in I’d make that part of your LP regime

I also agree with Chakster. Another issue is the limited production volume for current vinyl releases. Compared to the huge numbers produced for a given release back before CD, and now with way fewer record pressing plants, these limited runs and tight production schedules don’t allow for the same level of QC sampling and production process optimization. Granted there was junk produced even "back in the day".

The noise you are referring to is due to voids hidden under a thin layer of vinyl. In haste to crank things out or due to sloppy QC, not enough time is allowed for "degassing" of the blank while the vinyl is still semi-liquid. Play the record a few times, the vinyl is worn away and the pit below revealed with attendant snap, crackle, pop. Sampling and good QC would allow process step timing to be optimized to ensure a nice uniform slab of vinyl with little or no void spaces.

I am mostly as skeptical about audiophile vinyl releases as some others are about the value of so-called "hi rez downloads". Just another money grab. Of course there are always exceptions. The quality of the source material is one of the keys as has already been noted. Some labels seem to be more dependable than others for putting out a quality product.

I mainly listen to digital sources but have been carrying around boxes of records for 30-40 years. I still enjoy buying the occasional piece of old vinyl...and I don’t mean first releases exclusively. It’s a pleasure to put on an LP that is 30, 40 even 50 years old and enjoy great sonics and a quiet surface. It is possible. Case in point a recent antique store purchase of Al Stewart's "Year of the Cat" for like $5 bucks (some will no doubt say I overpaid!).  They did know what they were doing back when vinyl was king.