There won't be any magic bullet solution. Specifying text size in terms of pixels gives you tiny words on super high resolution iDevices or even modern laptop screens. Specifying size as an absolute via points or inches/cm doesn't work for users lacking the visual acuity to see that size. Specifying size relative to a user-settable device default only works for users savvy enough to find that setting. What we've got now is a mixmash of the above, where devices treat an absolutely-specified size as a baseline to scale from via zoom controls.
But hey, web font scaling is still twelve parsecs better than the original option of going out to buy the large print edition of whatever you want to read.
I also use my own style sheet, with my own choice of font. I use a slightly modified version of one of the w3c core styles.
In Firefox, I just set a my own font, a minimal font size of 16px, and my own link, background and foreground colours.
The web to me is just plain ugly outside my browsers.
I am now on Chrome which zooms uniformly and when HackerNews comments are just barely readable, the 'reply' links seem to be twice their size, when in Safari they were the same (minimum) size. Neither approach is pretty. :(
(There are workarounds but they shouldn't be necessary.)
You can always cut and paste instead.
I've been zooming since Netscape.
No privacy in the office for me sadly.
HN is unreadable for me without a little fine tuning.