Potential Sound Quality From 1950’s Microgroove


Hi All,
I’ve been modifying a Thorens TD 145 MK 1. After I built and installed a three inch hard maple plinth, the tonearm lift went kaput. I then upgraded the tonearm cable, upgraded the TP 16 tonearm headshell, a Herbies Way Excellent record mat, Herbies tenderfeet, dampened the insides and loaded a Audio Technica 33 Mono Anniversary Cartridge. I’m using an ASR Mini Basis Exclusive MK 2 Phono Amp.
So at least 97% of my record collection is 1950’s mono microgroove vinyl. I’ve been thinking about upgrading my tonearm. I’d most likely purchase a Sorane TA 1and then would eventually hope to upgrade my mono cartridge at a later date. But would I benefit, when the records I’m playing are nearly ancient with respect to their sound quality? Remastered mono vinyl is a consideration but those are limited in number when compared to stereo reissues. Any thoughts are appreciated.
goofyfoot
The antiquity of your records is very fine, condition withstanding, of course.                 I imagine you have some great gems there! You collected them for a reason, you well know. I won't weigh in on specifics, others better at that than I certainly will, (thanks) Improvements will enhance. Good luck.
isochronism, there are some I cherish. Many are so rare that I’ve been unable to find other copies on discogs, eBay, etc... And they are all in very good condition. Some still had shards of vinyl around the edges from when they were cut. 
Some of us have a REAL affection for records, and to us they are worth the extra care and possibly bordering on obsessing over them. They can dial in your emotion symbiotically with the music. Your primo examples are worth cherishment.
I do have to wonder though if improvements from a tonearm upgrade will be subtle or great. But you’re right to think that I will never rid myself of the ability to play vinyl. 
noromance, are they still available new? Jelco has closed it's doors. I might be more inclined to recommend one of the Ortofon arms. 

Goofyfoot, you have put a lot of effort into your turntable, forgetting about sound quality, it deserves a new arm!
Jelco new series is good ones but their effective mass isn't the big one.
Older Jelco series or Sorane TA is better match for mono system.




From what I hear, Jelco is no more and I can get the Sorane for what the Jelco would cost me. Jelco made Mission tonearms and Thorens owners liked them a lot. Also, SME would be a solid choice but their prices are too high. Of course, then there is the matter of installing it.
The Triplanar is one of the easiest tonearms to mount and runs circles around the SME IMO. Not cheap though, but its so easy on the vinyl! I paid way more for my records....
I think improvement for mono can be achieved, but subtle.

LP's with grooves compatible for advanced stylus shape would benefit from change from spherical or elliptical. Most flexible would be a MM mono body with various stylus options you can swap into the cartridge for a specific lp, I may go there myself.

I would coincidentally think more about what would improve your stereo lps, small qty existing, and future. 

that might lead you to consider a longer arm, changeable headshell, two arm deck

ease of VTA adjustment might be a consideration when choosing an arm
In my current state, most higher end options are cost prohibitive. The Sorane would be about $1,500.00.