Thats very hard to say without seeing what you have build. But lag is generally caused by having too many things inside the map. Could be too many items, too much code. So look if you can simplify parts of the map. Also need to check WHEN it is laggy. May maps usually lags the first 2-3 seconds quite hard but then, once all the is loaded they play reasonably. Also need to check on diffrent headsets. Q2 is most laggy, Q3 less laggy and 3S even less.
This being said, I think this here is the wrong place to ask these kinds of questions. The builder forum is here to show case your builds...