Level 16 Rogue - I'm allowed to role 5 or 5.5

We're coming back into some characters and the DM is allowing us to play 5 or 5.5 rules with them and is leaving it up to us to manage that (we're all experienced players and dms, so we can figure out any oddities of mix/matching these as they pop up). Most of us are re-rolling our level 16 characters to better fit the party and story.

The party is almost entirely martial characters (barb, fighter, ranger, cleric, tanky paladin).

My character is traditionally a swashbuckler rogue and I'd prefer to keep that since a full switch to a spellcaster just doesn't make sense for her story.

So in re-rolling them, if I went with 5e rules: I was thinking of going 3 levels fighter, 1 hexblade, and 12 levels swashbuckler.

But after looking at the 2024/5.5 rules, it seems like it might be better to just go full rogue so I could have full access to all of the utility of cunning action and play more of a support rogue for the big hitters. It seems like it might be more fun to play as well.

I haven't played the new rules yet, so I'm a little hesitant to jump into it in what is a fairly long campaign arc at this point. Is there an obvious choice here? If not, I'll probably go 5.5 and am open to any suggestions or links to discussions.