OP - Everything you mention is what I do. It allows you to buy THB as and when you want to take advantage of the exchange rate, as opposed to "having" to buy THB when you need to. I buy THB in small or large amounts multiple times weekly, or even daily - if the rate is actively moving positively.
EDIT: You also need to hold your domestic currency in Wise to do the above. Otherwise you must initiate a payment transfer to Wise for each transaction. I usually dump my domestic currency into Wise in bulk once or twice a month, depending on my liquidity and ROI etc.
The worst scenario is you get an average rate across a time period rather than buying in bulk on any one day. On several occasions I've converted THB back to my domestic currency because the THB strengthened and I had a surplus - make a quick $500, and then hope your currency strengthens.
The transfers from Wise FX account to my Kasikorn bank are virtually instantaneous, even after banking hours and weekends/holidays.
The Wise card is handy at supermarkets, malls etc. No fees. No good for ATM cash though, as the limits and fees are not practical. You can also get a Wise digital card - good for Lazada, shopee etc.
Sidenote - when dicking around in the Wise app checking exchange rates of various currencies, be careful before you press the confirmation button. I once inadvertently bought a truckload of Kenyan Shillings. Luckily I got out of them after a week at a minor profit, about enough to buy a pack of Marlboros.