What about his true current stage?
Put your ‘love feelings’ for him aside and think if a marriage with him really has potential.
You should make sure he is really past his past and growing in the past few months.
You should really some get some information from others on him before you actually start or continue to date. Perhaps he has a chavrusah or Rabbi? Maybe you have a male family member to make some research calls for you? Older sibling, father, grandfather, your rabbi or even female teacher/rebbitzin?