Figured bass notation is already long dead, but musicians carry its corpse around to show off that they squandered valuable moments of their lives learning it. It also creates needless ambiguity. Is
I7 a dominant seventh? Not in figured bass. Just try notating G7b9/B in figured bass. Yeah, let’s bury it already. And it can be so easy:
V9:2. You may have already guessed this is the dominant 9th chord in 2nd inversion. Easy.
ii7:3 is Am7/G in G.
I7 has a flat 7th on the tonic.
Imaj7 is the diatonic variety.
You are freed to do Roman numeral analysis with some sanity.