I've had a TS-520S with a vertical antenna since I became a ham. I
finally have an opportunity to upgrade, and I'm looking for a used
digital rig that will offer some key features. Unfortunately, I'm not
familiar enough with most modern feature sets to help narrow down the
field of eligible rigs. The key motivators for my desire to upgrade a

1. Better filtering. SSB is ok on the TS520, but the CW is a little
too wide and the correct filter would buy 1/3rd of a used rig!
2. WARC band support.
3. No tuning. (This isn't a really big deal...could live w/o.)
4. General coverage receiver.
5. Antenna tuner if possible. With only a vertical, most of 80m and a
lot of 40m are too high of SWR.
6. Computer interface. (This is more icing than cake.)

Above all, however, would be the expectation that the basic TX and RX
quality be comparable to the TS-520S.

I'd like to know if there are some features of more modern digital rigs
that I will find useful. Keep in mind that my operating habits are
casual ragchews and some DX chasing, but not contesting. Any additional
criteria for my search would be appreciated, and feel free to endorse
rigs as well!

Thanks,
Jim (KB9DNA)