I don’t know about upgrading if it will help,
but from my experience, most slow performance can be fixed with improving your app structure.
Are you using the database a lot? creating adding removing new things …etc?
Are you using “do search for” a lot?
in general it is always better to use custom states, less usage of the database …etc ( not only this but it is a start)
search on the forum about performance , there a lot of good stuff here about this.
Maybe it is good idea to post a link of your website here so people can give you better tips.