I dont think they were telling you to not spend money for the present, but to always consider your future in the equation. However, the show also made it clear that there was no universal answer.
As for falling in love with your asset, I don't think Kimimaro did. The only girl he loved was Hanabi, and the show gave you a few hints. He definitively cared for her, but it wasnt love.
Despite the last kiss, I think Msyu represent Kimimaro's future daughter. Based on everything we saw, there seem to be a direct connection between asset, and the entrepreneur's family.