I am not giving advice, I am simply stating a fact. I cleared the overstay's at the airport each time and i have never had any trouble about this since.
I have been asked for proof of onward/return travel even with a visa. In Luanda, Amsterdam and LHR,( granted this all happened over 10 years ago). A visa does not guarantee you entry into a country, If the airline feels that there is a risk, they are within their rights to deny you boarding.
My paperwork never changes, same every year so just photocopied. then only thing I need to get is embassy letter verifying my pension which is easy to do and takes a week. 90 day report is a nice motorbike ride once every three months.As for things going sour, most men lose their asses anyway in UK and other "advanced" countries.
It worked for me three times out of the 5 times I tried it , so 60%. However its a nice motorbike ride out to immigration where I live and the in person report usually only takes me 5-10 minutes.
Unfortunately the archaic and chaotic Thai system of addressing is to blame for this requirement for a map to your residence. I often wonder how Thai post manage so well.