Nelli Vids lightning usually doesn't cause much lag, I made a machine with commands that summons dozens of lighting bolts per second and the frames don't drop at all.
M -14000000000000000000000000000000000000000000000000000000000000000000000000000000000000000 000000000000000000000000000000000000000000000000000000000000000000000000000000000000000
Tips for PVP: water bucket for fall damage before landing lava bucket flint and steel fishing rod for damage from afar bow and arrows ender pearls snowballs a stack of blocks for blocking