1) General subject: I believe so, by my reckoning, in my eyes, in my judgement, in my view, it is my belief that (...), to my mind, to my thinking, what I say is, in my opinion, to me (вводное слово), speaking for myself, to my way of thinking, as I see it, off the top of my head, I think
2) Colloquial: sez me
Универсальный русско-английский словарь. Академик.ру. 2011.