Nicol Bolas, Planeswalker is really good in this deck. I think Intet, the Dreamer would be beautiful in this deck also Dig Through Time. I'm really interested in your choice of using Meren! mind elaborating on it?

when it comes to counter spells I think Overwhelming Denial is good but maybe adding Mindswipe would also be good!

CinnaToastKrunch I agree about Nicol Bolas, Planeswalker being a solid fit in the deck. I want to get him! I think Intet, the Dreamer is a fun creature, but I haven't been able to get him going very consistently in my Animar deck.I have Meren in the deck because I originally had several sac-outlets, which allowed me to control how often things died. I also think that Mizzix of the Izmagnus and Meren of Clan Nel Toth work very well together. originally I had Ezuri, Claw of Progress in here as well to boost the experience counters. Now that you brought Meren up, I'm not sure that she(?) belongs in here afterall. However, it can be powerful recursion, and can bring back key creatures.I do like Mindswipe, I'll have to look at how it plays in this deck.

Do you see any other cards that might be a little weaker in this deck?

if you're really looking for cards that go well with Yidris you can look the cards up on EDHREC. it's very helpful! I would highly suggest Whispersilk Cloak and Lightning Greaves

Thanks for the input! What are your thoughts about Meren?

The only problem I see with meren is that she may not be out too long and if you are dependent on her you may not be getting her out. I see her best as a commander tbh. Yidirs focuses on cascading and storm.