Of course I've been up all night! Not because of caffeine, it was insomnia. I couldn't stop thinking about coffee.
First is about the immediate take card action. Can I take the card from the tower where I already have one of my colored family member? In rules it only states to pay 3 coins if tower is occupied but nothing about it beeing occupied by me
Yes you can. Just like you can place your uncoloured family member into that tower. If you want think of the immediate action as uncoloured.
Second one is about permanent effect that increases the value of a specific action - when I have two characters that increase the value of the same action do I add them together? We played that they do because we didn't find any indication that they shouldn't but I wanted to make sure.
Yes, you add them together.