Hmmmm IEO is a little bit unlike ICO because i don't think the exchange plays a huge role anymore in terms of CEX
As most sales are now moved into DEX for sales/Bounce, i am not sure if we consider Dex sales under the category if IEO
But all these potential coin are able to fetch up pretty solid ROI regardless if they are ICO/IEO/Airdrop/Yield Farm

As long as they can prove that they can be valuable in the long run, their value will preserve and goes up