If you want a DX-style synth, I'd highly recommend getting Yamaha Reface DX for about $250 on Reverb.
It's the most underrated synth of all time. The controls on it make FM synthesis fun, and you can change the sound in real time. It's compact, I've brought it with me anywhere from airplanes to deserts. The built-in speakers are good enough to jam with anyone, anywhere. Everyone who's touched it loved it. It's worth its money for the e-piano patch alone. And on-board effects take it to the next level (tell me of another synth at that price point which allows you to chain two Delay FX!).
FM synthesis can be done purely digitally, and Dexed VST will do a good job replicating DX-7. Reface DX offers a compelling reason to buy a hardware FM synth: it's an instrument that in the long-term will help you transition into live performance, and in the short term will incentivize you to play with it, and learn FM.
Oh, and it's a great 3-octave mini-keys MIDI controller too.
Cute as it is I'll take the extra knobs and the motion sequencing on the Volca any day of the week. It's a very interesting contrast to Yamaha's modal UI approach (where you can easily switch between parameter sets but have only two soft parameters available at any given time).
Interestingly Yamaha documents the CC codes for the Reface DX, so you can use an external controller with knobs such as an Akai to go wild with altering the patch while you play.
I’ve only done a little bit of this, but here’s a video where the guy is all over it 12 minutes or so in https://youtu.be/Xt-tmIMCxTk
Hardware...Get a Volca DX-7 clone for $150, a Behringer analog synth clone for $300, and a nice reverb/delay pedal. Protip: older and cheap mixers will give you some 'secret sauce' in terms of lightly distorting and compressing your signals. Get Mackie if you like a rough sound, Tascam if you like it a little tinny, Spirit or Allen & Heath if you want warm.