There is no law or rule limiting visa exempt or tourist visa entries. You can do it until you can't. For some that's 6 or 7 entries in a short span, for others in 2 or 3. You are correct though, if youre going to come regularly, get the proper visa for it
no problem, there is another route you can take if you are determined to come by visa exempt or tourist visa before applying for the DTV. You can contact an agent such as
just go direct for the DTV. Even with an SETV you could be pulled out of line, questioned and then denied entry. Its upto you what you do, but personally I wouldn't risk it as a visa doesn't guarantee you entry, it only increases your chances of being allowed to enter
You're flagged in the system and each time you enter now without a visa or even with a short-term visa your chance of denial increase 10 fold. I suggest looking at a more long-term visas before returning such as the DTV