What letter comes next BCDGJ?

Question
What letter comes next in the sequence 'BCDGJ' ?

Analysis
Sequences are often arithmetic, but there does not appear to be an arithmetic sequence to this set of letters.

The missing letters are
A_ _EF_HI_ . Notice that all these capital letters are formed solely by straight lines, whereas _BCD_ _G_ _J are all formed, wholly or in part, by curved lines.

A complete list of all 'straight-lined' letters in the English alphabet is
A_ _EF_HI_KLMN_ _ _ _ _T_VWXYZ.

Result
The list of capital letters which have curved lines is
_BCD_ _G_ _J_ _ _ _ OPQRS_U_ _ _ _ _.

Conclusion
The letter letter that comes next in the sequence 'BCDGJ' is the letter O.