I think they should remove egg and snowball from nornal porjectiles because noobs can easyly hit us into the void. The bows are ok i think but there should be less arrows because of bowspammers.
You may as well say that the bow should be removed too then. They are pretty much the same thing, only the snow and eggs do not inflict damage, but can be used to send someone flying off the edge. I do not see a problem with either, and if you get killed by them, it is your own fault for leaving yourself exposed enough to be shot off with a well-aimed egg spam. Like I said, snowballs and eggs are a good method to shoot someone off the island if you do not have a bow and/or arrows. Furthermore, snowballs and eggs are part of Skywars in my opinion.
I also thing they should remove all the lava because sometimes when we are in pvp they will put a lava bucket and we will become slow and die in lava.
No, lava should not be removed from Skywars. Using lava is a tactic that is as valid as the others (golden apples, bows, spleef). It is Skywars so there are not only sword fights - you can PvP, however, it does not have to be the only way to kill your enemies. The great variety of ways to play Skywars is what makes the game more enjoyable. Removing the lava in Skywars is basically removing a tactic.