As noted, pretty variable answer depending preferences, type of mining even (e.g. 3P - plat, pallad, etc , zero refinery mats-only, ice ring, low combat vs hires mining, etc)
I'll just give 3 wallet based answers though - if I was only audience that had to pick
1. lower end $$ = Asp (good # of hardpoints for mining lasers + optionals, decent cargo/limpet storage, good internals for mining build)
*an yea, I'm not saying Asp is technically a 'low' end ship, just saying for mining I really wouldn't go in a lower level ship - earn credits till you can get an Asp for mining. Just because you CAN mine in a hauler doesn't mean it makes a 'good' miner.
2. mid end $$ = Python (pretty much do it all ship even though labelled mid end $$, can combat mine hires or zero weapons load out, tons of space, internals, hardpoints, every mining scenario can be oufitted with room/power to spare)
3. high end $$ = Anaconda (not saying is huge cut over Cutter or Corvette, just if I had to pick a big3, Anaconda has slightly more mining capability)
There's no real reason you NEED to upgrade from Python to Anaconda, but it does give longer endurance to mine as well as ability to truly match collector speed to mining laser speed. With an python you gimp cargo space if you go 11 collector build, whereas Anaconda you can fit 11 collectors and still have ~200 tons for cargo/limpets)
Anaconda isn't exactly high maneuver ship but it's ok and tons better than T9. That's the reason I wouldn't include for my persona list only a T9. Great ship with internals galore and cargo room, but a lot of old mining, not sure about 3.3 new mining, has increased efficiency if you can maneuver and thrust at decent rate. T9 is still great ship, just for my style at least, slower mining and therefore less mats per hour.