While I have a 50 amp line (which means I am charging at 40 amps continuous) and appropriate Chargepoint Flex EVSE, I usually only take a couple of hours to get back to 80%. So unless your charging window is pretty small, your 30 amp EVSE should be adequate to do overnight charging and get you back to 80%.
BTW, what power (amp) line is going into your EVSE? Unless you have a 50 amp or greater line going in, you will have to upgrade the electrical line as well.
There is a problem with Hyundai/Kia/Genesis chargers on L2...you most likely will only get about 9 kw charging. So...IMO, unless you are anxious to future proof your home, you can probably avoid spending the money on upgrading the EVSE. By the time you need to do so, the technology will have changed again. For example, inductive wireless charging,. And solid state batteries, etc. might require other changes. So waiting is, again, probably a better bet.