We always approach trauma from the place of irrational behaviour and mental/emotional instability but in reality, it could be the things you see as green flags! Sometimes, your partner's sweetness is a trauma response. These things go beyond insecurities and fears. Yes, you are not a therapist but if you are honest with yourself, you will see the need to interrogate some of your partner's green flag.
Sometimes, the effects of a previous toxic relationship could be positive for the new partner but nonetheless detrimental to you.
I have realized that besides projecting their fears on their new union/partner, people also try to make up for their past inadequacies in the new one. While this appears like your partner is thoughtful, they're merely trying to plug a hole that existed in their past and may not even exist now.
For instance, if someone was broke-shamed and jilted a person because of paucity of funds in a past relationship, that person may want to go out of their way to be financially responsible/present materially. Consequently, they do everything, including depriving themselves of good stuff, to make sure they give and get things for their partners. While you're happy, your (wo)man is generous, they are trying to not allow lightning strike twice.
Conversely, people who have been financially abused in past relationship could choose not to ask for things or even be wary of receiving things from their romantic partners. So while you think you have an understanding (wo)man, you are actually with someone who's dealing with the trauma of financial abuse. Are these things good? No. Do we even know? No.
I believe strongly that you need to have deep conversations with your partner. If you have a partner who always gives and gives without being bothered about not receiving, even when you can clearly see it is hurting them financially, you might want to have a conversation with them. If you are with someone who doesn't ask or reluctantly takes, sit down and talk.
This is not just applicable to finances. Sometimes, you need to study your partner and see what they do in a manner that’s excessive, impulsive or to their detriment. Do not be blinded by what you think are green flags or ‘sweet’ behaviour. Ask questions.