USED RECORD GRADING- What's the Problems?

There seem to be many disconnects and bad experiences between sellers and buyers. Would the secondary market benefit from a new, and revised, grading system (beyond the Goldmine standard) that combines a visual-grade and a play-grade? Also, would it help to have grade tiers that are more granular like is used for coin and stamp grading? Or will this market have to rely on trust in the seller? Let me know your experiences and thoughts. 
5d8015ac 008e 4b30 a925 6dcb77e47c3fvoiceofvinyl
Post removed 
While the current grading regime is far from perfect I can’t see how any alternative is better. Especially as each of us is different in terms of what we expect. For example I’m really quite tolerant of tics and even light scratches but even a hint of hf breakup from prior mistracking sets my teeth on edge. Also depending on the setup different problems will manifest so even play grading will not mean the same thing to different people.  
Good luck w/ that. Even play grading is subjective. In some cases, I'd prefer that the seller not play it or purport to clean it. Just spin it to tell me whether it is warped. I had one seller tell me when i asked about warps: "You'd have to be an idiot to sell warped vinyl"
Guess what? 
I try to do the due diligence before I press buy- i have a dialogue with the seller thru the messaging system if a platform or via email if a store. The responses are often telling. 
I consider myself lucky. I've had some misgraded records but overall, I've come out OK on balance. I also do a serious cleaning when they arrive or at least before they get played. And sometimes re-clean, which can help remove grunge that sounds like groove damage. Sometimes it is groove damage. 
When seller with good feedback says NM I automatically assume that it will be VG+, and in 90% of cases I am correct. When it says VG+ it is quite a range that I got - from VG- to true NM. So I usually expect VG+ record and the right to return it. No need for new grading system, it would only confuse the issue further.
I talk to sellers too in some cases before buying.
Never any problems in buying used, always ask seller questions before purchase like I do with any other audio buy.
When I buy on-line I always just go into it knowing the grading is going to be off by one or two grades. So, a MN- will be a VG+ or VG, etc. I price accordingly. If the price is acceptable for the lowered grade, I'll buy it. That said, I don't buy true collectors records. Most stuff I buy cost less than $20 ea., so I'm never out any significant money if the grading is way off the mark.

Honestly, I have a bigger issue with new $30 -$40+ records that have noise or defects.
Post removed 
all over the map...but in general I appreciate a play grade also...acknowledged that setup and subjective assessment are present as w visual grading...

i grit my teeth on scraping , less so ticks and pops....

just got an unopened MFSL Rock of Ages that has some really rough patches and disc one has a ski jump warp.....hard for seller to know....$32..... oh well....
I use Mint only for sealed records. That does not mean that the record inside has no flaws, as noted by tomic601. On sealed recrods of value, I offer buyers the option of having me open it after they buy it. If the record is not MINT, then I give them options. So far, no one has taken me up on that offer. 

Occasionally I will use Mint- for a record that has obviously not been played or is perfect, but opened.

NM for me is a grade I will give records that are virtually flawless. They may have a few very light and hard to see sleeve micro-lines. It should play dead quiet or with just a few light tics which could be inner sleeve dust or even static. 

I granulate my gradings from there and offer a visual grade and a play grade because they often differ wildly for various reasons.  

What is the "scraping" you mention? Is it cue-burn or groove wear? I am always adjusting the language I use to describe sonic and visual flaws. 

Thanks in advance.

Yeah, I understand scraping as groove wear or groove factory defect. I have a few records with that in the beginning of each side otherwise nearly perfect. They are first release Japanese promo records from 70s and sound better than anything I know of. One was absolutely new and sealed.