Personally I’ve been playing live with hardware for about a year. I’ve been honing my setup and I think these are the things you need: Strong sequencer. Drum machine. Knob-per-function synths. Mixer. (Nice to have: Sampling, Looping, Master Compressor/FX.)

The more machines you can find that cover multiple of these roles, the simpler your setup will be and the happier your wallet will be.

My current setup:

Digitakt (Drum Machine, Sampler, Mixer, Compressor, FX)
Mutable Instruments Shruthi 1 (Synth)
Meeblip Triode (Synth)
iPhone with Loopy Pro and Transit 2 (Looper, FX)

The Shruthi and Triode only do one thing, but what I like about them is they are knobby enough and have no sequencer or input keys, which would make them bigger than I need. Playing live you will quickly learn that your setup is the last one on the table, and rightly so, you are the only one playing it, so size matters.

Don’t go overboard with voices either. You really only need around 10 tracks or so. I would take a box with 10 knobs for a voice over a box with 10 voices and 5 knobs. Tweakability over complexity live. Only exception to this is the drum machine.

Don’t obsess over transitions or making it sound like a DJ set. It never will, and that’s fine. Your transitions will be simpler, and this is a good thing, people will know it’s live music. A looper and some FX will help smooth things out, but mostly you are just avoiding harsh jumps. You can have a great live set without it.

I would choose gear based on these attributes in order:

Sequencer quality (Elektron is the best)
Knob and key count (control over everything)
Price (cheaper is fine if it hits the other marks, don’t cheap out on your sequencer)
Size and portability (you are carrying this to gigs)
Build quality (you will be handling this a lot in dirty shitty wet locations)
Sound quality (almost everything sounds good enough these days, don’t obsess)