1/2 I have another headcanon, (based off of the scene where Beast gives Belle his enourmous library) that Beast is all about grand romantic gestures. He's the kind of guy who proclaims his love for his wife from the rooftops, and he probably belts
Yes, the Beast/prince is definitely the kind of guy for romantic gestures, he can pretend all he wants that he’s aloof and dignified but really he’s a total sap at heart and he doesn’t care who knows how much he adores his wife. Some of the other nobles find it sickening that they’re so happy together. (Mostly because they’re just jealous.)
I do like to think that the Beast/prince is kind of shy about singing, though, despite having a nice voice (hence only having the one verse in “Something There”). And Belle kind of has to coax him out of his shell in that respect. I love the idea of the Beast knowing how to play piano (thanks @theteaisaddictive for that headcanon, it’s sort of a plot point in her story “A Rose’s Thorn” because he starts teaching Belle, and it’s adorable). Maybe he would compose a song for her for their anniversary one year.
I don’t think he keeps one-upping himself in terms of giving lavish gifts, but he does always try to think of something thoughtful and insightful, because he just really loves watching Belle’s face light up with surprise and delight.