Hello Mizenor,
Do you have older kids now 
Thats what happened to me. A whole lot in WoW has changed. It felt overwhelming at first. Then I realized half the things I thought were new didnt even matter because they were part of older content. My suggestion would to be to start a new toon from scratch and just level through the stuff. It doesnt take that long. I actually did it twice. Maybe you could say 3 times since there were a couple half levels in there too. Also be prepared to look into Discord if you havent already as the has mostly replaced Gchat and Vent for voice channels. Its actually pretty sweet.
Anyway, for the guild! I would to have some fresh blood while you get your feet set again. Here is my normal post below!-
I am a returning player. I came back last spring. Apparently it had been 7 years since I was last online! I have really enjoyed WoW since then but one of the things I was missing was the social aspect of a Guild. I joined a guild for this xpac that I am very happy with at Tryhardish.
There is a wide variety of experience levels that lead to a more casual atmosphere. But, the officer team is knowledgeable and skilled while being dedicated to forming a positive environment. Avg age is probably in the mid 30s with a ton of working adults that want to game.
We have a normal raid team going that is open to all. We also just started an AOTC team and are currently 5/8H. Being part of that team is a little tighter, but the lineup is still being sorted out. The normal raid is Thurs and AOTC is Sat. Both are 10 EST to 12. If you want to discuss the raid team in more detail, let me know and I can hook you up with the lead.
Other then that, there is a handful of skilled players looking to run keys and also another group of players interested to start. I fall into that second category :). We normally have one or two M+ teams rolling around in an average night as long as its not raid night. Discord is active!
If that sounds like it might be a good fit for you, I invite you to check them out. Cheers,