In , I Don Klipstein wrote in part:

If you replace the ballast, best bet is to get a good 32 watt electronic
one such as Sylvania "Quicktronic" or the like from an electrical/lighting
supply shop.
And my favorite bulbs are ones with 835 or SPX35 color (3500 Kelvin, CRI
in the 80's - highest available without compromise of light output).

One thing I just remembered about replacing an old-fashioned ballast
with an electronic one:

With electronic ballasts, bulbs that are in the process of failing
tend to get very hot at one or both ends. I have known this to overheat
the "sockets"/"lampholders"/"tombstones" if those were not made to take
the heat from ends of bulbs in the process of croaking while running on
an electronic ballast.

This "end heating" sometimes gets even worse still when the last
remaining working bulb running on an electronic ballast is singing its
swan song.

If you replace the ballast (rather than the whole fixture), you probably
want to get sockets / lampholders made for or pulled from a fixture that
has an electronic ballast.

- Don Klipstein )