Tonearm adjustments on the fly

Oh, sorry, there is one thing I did miss that should be fixed. The two things you want in an arm are VTA on the fly and a hard wired integral phono lead. Cartridge output is the faintest in all of audio. The last thing you want is a delicate signal going through a lot of connections. So hard wired phono lead, no detachable arm wands or head shells. 

Probably not what you’re looking for but my Schiit Sol has all of those features and punches way above its weight in the sound quality category. Mine was the last run of pure b-spec after all their beta testing improvements and then went through with the recommended upgrades and a great cartridge for my budget. Biggest difference in the sound quality came from proper vta/sra and the azimuth. Getting that right will get the tonal balance spot on and makes that center image snap perfectly in place. I know lots of the hifi crowd scoff at Schiit for their focus on reasonable cost gear but holy crap does it sound good. If you like tinkering to always try and get a little better performance and if you can get your hands on one, they’re worth it for sure. Just my thoughts as I sit here tapping my toes to the music.

VPI arms are easily adjusted....once you found what you like why bother

This last reply beat me to it. Most VPI tone arms allow VTA adjustment on the fly. And decades ago Technics produced some gorgeous tone arms with infinitely adjustable VTA that felt like adjusting a lens on a fine camera.

Most of us adjust VTA for best sound so it doesn't ultimately matter in this case what SRA is.

By the way always adjust vertical tracking force 1st. Changing VTF will also change VTA. In fact if your arm doesn't have fine vertical djustment you can use VTF adjustment for fine tuning VTA if your arm permits fine tuning VTF. First set up the hight of the arm for a VTA that sounds good after setting the VTF in the middle of the recommended range. Then very slight adjustments up and down of VTF are also fine VTA adjustments that should have no significant affect on cartridge tracking.

OP's question about what do other tonearms do?

MOST VPI unipivot arms (NOT the stock Classic 1 arm) lift the entire base on which the pivot is located.  The mechanism uses a fine-pitch screw to accessible on the arm base to make the adjustment.  Allos good on-the-fly adjustment.  

For a lot of tonearms with a "standard size" arm pillar, there is the Easy VTA base.  It replaces the original tonearm base with a hole and set screw for the arm pillar.  A fine pitch screw system using parts from a micrometer is used to gently raise or lower the arm at the arm at the pillar while the record is playing.  Once the correct VTA / SRA is attained, a set screw can be used to lock the mechanism in place.  Works GREAT on FR, Grace, Jelco and (IIRC) Linn arms.  I'm using it with a Jelco TK-850L.  Best combination I've heard.