Hey there!
Yes, absolutely! Serious Sam is an awesome, fun game and it has inspired us a lot. You know, Egypt, haha. It's one of our main references along with Ziggurat or Rogue Legacy.
About developing with Unity: it's fun as well as it's challenging sometimes. We love using stuff like shaderforge or behavior tree, because we save a lot of time, but in some areas it falls a little short, as you said.
Thanks a lot for your comment and congratulations on your game, man. Looks really nice and I already love that dog, haha. Keep on that great work.