Like has been said it will help what you work with ITB to have a good front end...some decent mics and some decent preamps. You might get this from a decent mixer or outboard preamps. Maybe you still try to find that decent smaller mixer. I shied away from suggesting the Tascam M-300 series because you were so adamant on a 24-track tape machine (the M-300 series only have 4 subgroups), but maybe you consider a hybrid studio like so many others here do...it gives you the power, ease and flexibility of the ITB world, but the tactile work process and additional possibilities of the analog medium...and typically involves an analog mixer with a smaller footprint (since you don't typically need as many subgroups or channels), and a smaller capacity multitrack machine (like a 1/2" 8-track...the track width on a 1/2" 8-track is really close to 2" 24-track, but SO much easier to maintain and to house and find tape...MUCH more affordable) and maybe a mastering halftrack machine. It can be overwhelming just dealing with the wiring for a 16 or 24 group desk and a 24 track tape machine. So, back to the Tascam M-300 series...I have consistently found these mixers to be reliable, great sounding, and with a great feature set...there are things you don't know about in terms of how these things were built and corners they began cutting in the late 80s and 90s...smaller pots with plastic shafts...horizontal PC board wave-solder construction with surface-mount parts instead of vertical per-channel boards with through-hole components...I think the M-300 mixers are a tremendous bang for the buck, but they are 4 subgroup boards...which is perfectly fine for project studio and 8-track tape or DAW front end. The M-308 is easier to haul round and to find room for in your home. The M-312 adds 4 more input channels and a well-featured talkback and monitor section, as well as two additional AUX busses on the group sends/monitor returns, but is that much bigger and heavier. The M-300 was made before they really started shrinking the control surface real-estate on project studio mixers (which was done to reduce costs). This means more weight and size, but much easier to find your away around and get your fingers around the controls. And they sound great and can be much more easily worked on and repaired, etc. Look for the 'B' models which include phantom power.
You could also jump into something like this:
Soundcraft Series 800B Vintage Mixer | eBay
These are a respectable modular constructed board...a studio and live workhorse that is respected and pretty well supported to this day...good sound..but way beyond your size and weight considerations. And what likely happens when you get something like this is it needs work...you can find them already gone through but you pay the price. If you find one that needs some work, a mixer of that size has a lot of circuitry to go through and troubleshoot. It takes time and money and I just want you to think about whether you want to spend weeks/months/years going through your mixer and getting it back into shape, or making music. I've spent years doing the former...you might have more time than I do to plow through getting your gear you find into shape...but its taking me years and years.
So I'm just trying to offer some options that might keep your analog possibilities open with an affordable but effective hybrid approach. I think the Tascam M-308B and TSR-8 would make a great analog partner to a DAW setup...relatively compact, well built and featured, and good sounding...affordable.