Hello everyone, currently working on a 3D Sci-Fi tower defense game Constellation Defenders for PC and Mobile.

Constellation Defenders

I would like to know what has worked for you in terms of playing TD games with ads that weren't too annoying.  I just want to find the perfect way to implement them so it doesn't hinder the overall experience.

So far, I was thinking of releasing the game for free with skippable ads between levels.  There would be an in app purchase to remove the ads if the player feels so inclined. 

Let me know what you guys think and thanks in advance for the feedback!

Second Idea I had was to double premium currency rewards at the end of the level if the player watches the add.  The game will not be designed around this feature however, it will just be a QOL addition.  I don't want it to feel like a grind fest and definitely don't want to make players feel like they have to watch ads to progress.

Reason I'm asking is because I wanted to release the game F2P. 

Let me know what you think  and thanks in advance :)