Shrek looks fine, just older. Definitely won't be a very nostalgic design.
But everything else? I'm not so sure. It might end up like Arctic Dogs where the movie flopped so hard due to the lack of interest and also from bad advertising. (don't get me wrong. I personally like AD despite it's bad story, as you obviously know I like Jade Foxston alot).
And AD also had big name actors used to. Such as Jermery Renner, Heidi Klum("Your Old,German and married to a SEAL." -Robot Chicken), Alec Baldwin and a buncha other big names(like John cleese. Who actually sounded like he enjoyed doing his acting as Otto). Shrek 5 as you mentioned will have Zendaya(whom I never heard of). Thankfully Shrek 5 will have the OG actors like Myers and Murphy.