I think think replacing URLs with alternative front ends has some downsides for this bot. Sometimes they are unreliable and they are not so optimized on mobile (don't open the app if you have it installed). I think it would confuse some users.
Otherwise I like the idea, but not sure how to integrate them without these downsides. 

 I just provide both links when I can, or I use a redirect.invidious.io link since they offer official YouTube as one of the redirect options 

 Not sure if there are services like redirect.invidious.io for other frontends like redlib