The cats should be out of their super rowdy kitty phase where they keep making mishief faster than you can look. Then it's fine as long as you make sure to not leave the cat alone with a lit candle for an extended period of time, just so you can immediately put the candle out in case an accident happens - fires are only fine and funny as long as they're not endangering anything. It's new, it might be playable, so ofc the average cat will come closer to take a look and possibly some boops if possible until they know what that candle is.

From personal experience you don't have to keep sitting right next to the candle (I still did for the first couple of times because mine came close) as long as you're in the same room so you can come running ASAP just as safety precaution for worst cases. Those candleholders you mentioned sound good, I have something similar here (some big decorative glass/plastic things where candles can be put inside, not true candle holders though). Definitely helps with the peace of mind though if your cat ends up finding candles boring they won't be necessary.