Paragon and renegade were never really consistent, even within a single ME game.
IMO paragon covers the entirety from lawful neutral (trying to arrest exogeni scientists) over lawful and neutral good to chaotic good (dealing with Helena Blake or Harrot)
Basically paragon is mostly 'good'.
Renegade is even harder to say, as it ranges from lawful to chaotic good -but shouting at people in ME1 (with sometimes lawful/neutral evil in there); then to chaotic neutral or evil in ME2; to it's ME3 incarnation of mostly lawful evil.
That's just for the 'pure' paragon/renegade versions.
Nowadays I literally make my alignment up before starting a playthrough, using either the old D&D system or 'what would person X do' -questions.