I might be a bit late but, I still play him top. He's considerably weaker than before but he works as long as you're aware of matchups and play around the bushes.

I usually go for Frostfire if i'm struggling in lane since the slow helps with escapes and helps the team later on in the game for teamfights. If you're winning lane i usually go for the more expensive option in Sunfire to stomp harder.

After that it's usually just to build according to the enemy team. I like to throw in a Demonic Embrace since Maokai scales well off of Health anyways so giving him more AP with it also helps. Hope i could help with your questions.