What is the likelihood of being refused entry into Thailand with a 6-month METV after a history of multiple visas and exemptions?

Have read through this Thai Visa advice thread regularly and just wanting to check the consensus of opinion about a 6 month METV. I am heading back to my home country and applying for the 6 month METV. I will have just finished my 9 month Edu visa and also have a record before that of multiple Visa Exemptions with air crossings from 2018 and 2017. If the 6 month METV is granted, how likely am I to be refused when entering Thailand with it? obviously an immigration officer can refuse entry at discretion but how likely would this be? I will of course bring with me 20k baht in cash, plus proof of accommodation with my partner of 2 years that has also traveled with me regularly. I am out of Thailand for at least a few months each year and live off investments and savings.

Additionally, how likely would it be to get refused a 6 month METV from my home country? Has this been known to happen? Thanks in advanced.