There should not be any connection/correlation between the past exempt stamps and the application of a TV at an embassy. The embassy look at past stickers, not really exempt stamps. But of course even with a TV in hand its still at the discretion of the immigration officer at the port of entry. In my opinion you wont have any problems given the info you have stated above.
In regards to how many TVs, as said above by someone else there is no written limit but embassies will start to raise questions if they see a build up of stickers. Usually its embassy by embassy but there have been reports of certain embassies even counting stickers from other embassies in the region.
Next time there is a post about Non O based on retirement I might have a moan about cheap charlie expats who look down on tourists and pass it off as advice ..lol. I assume that will be fine.
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