Thank you! Yeah I started to make a 4017 sequencer a few months ago but didn’t finish. I have a partial modular eurorack system with a SH-101 style MIDI sequencer in it, that accepts and outputs MIDI as well as CV (DIY version of Mutable Instruments Yarns). Korg SQ-1, Volca FM, Volca Sample, Pocket Operator PO-16. And still want to make a Beat707.com Beat NXT step sequencer.
But maybe I’m hoping to force those devices to be something they’re not. I should just work within their very limited step-resolution and do more live-ish performance recording. There are tricks to get extra notes with arpeggiators and or manipulating samples in novel ways on all of those devices. But nothing like old Yamaha sequencers etc. I might get a QY-10 (had one in the 90s) just to start with, you can record with a metronome etc, MIDI In/Out.
I started with tape and a Casio HT-500 synth when I was a kid. Yamaha keyboard with real-time sequencer. 4-track tape. Then Cubasis, Cakewalk, then computers started being able to synth things in real time, so I’ve used Reason/Live/Cubase and Reaper off and on for years (mostly Reason) with controller keyboards. The Nektar Panorama P4 etc interest me a LOT for a more hands-on feel and not using the mouse/keyboard/big screen, but I don’t have one. Was feeling uninspired by the god-like power of DAWs and VSTs. Maybe I could try Sequencer64, on a very mini Windows or Linux PC with a very small screen and use MIDI only. Also the Wusik SQ200 software is extremely hardware-like and I do enjoy it. Yes, something that had the power of a MIDI software sequencer from early 90s would be enough…maybe haha. Maybe just a second RPi with a sequencer in Raspian? 
Well there’s my life story haha, what’s everyone else use?