Hey Vic, welcome to NCWW.
I would question how 'practical' a round bedside table might work out, especially because by it's very nature it's usage tneds to be in the dark, at least sometimes. I am all for non-boxy furniture, but in this case I might consider a rounded front table with at least two or three straight sides (i.e cutting parts of the circle off).
Aside from my design perspective, just know that any amount of table top projecting beyond the base of the lags is far less stable - inch or two is perfectly fine, but 6'+ gets less stable. Helpful that this is a relatively low table. Answers also depend on the mass of the table. So I would at least minimize that overhang, especially if this is not a massive table. Anything can work... but it all depends on how much you might expect to lean on or press down on the edge of that table.... Can't give you a numerical answer, but a model made with 2x4s or 2x2s and your table top will give you a pretty good sense of what will work.
Keep us up to date with your design, fabrication, and final result.