Although this sounds primarily an issue on your side due to hardware, I do like your point.
However, many people I play with who use adequate hardware experience drops in frames in the lobbies and games because of fireworks.
In fact, I myself experience these issues even when my game has been and runs perfectly on my system. Sometimes a nice effect can be just too much. It also is rather noisy, as much as it is appealing, a little too nice can sometimes be a little too much.
Everything else runs perfectly fine, map loads, token spawning is all OK.
My friends were saying that perhaps that because of how many players now play daily on Cubecraft, the cubelet boxes when being used, display multiple fireworks constantly as many players in every lobby use them. My thoughts were that, an effect could still be used but a firework only goes off when the name and item is displayed. Another idea is to have the firework/particle/sounds only played/shown to the player opening the cubelet and a noise or quiet sound is played only when the name of the item becomes visible to the user of the cubelet. With this method, perhaps the system of One Player At A Time could be drawn out. Boosting efficiency and lessening irritation.
abfc2000, I would recommend you look into upgrading your hardware as the average player does not need to turn their settings down to the severe amount you do. I would understand a slight lowering and capping frame-rate but having to work with 2 chunks is just not recommended.
These games require you to see enemy islands, bases and other things. I do know that the fireworks and other effects have AN impact but not so bad as to your extent.
Thank you.