Getting the best out of your equipment depends on one very important thing that you have missed out: what you want to produce. If you just want to create instrumentals purely with the two synths you have, all of the equipment might even be a shade overkill. On the other hand, if you want to create complete songs with vocals and many recorded instruments, you might be falling a little short. It really depends on what you are planning to use the equipment for. And that will also decide whether you need to invest in more equipment or not.

About laptops/computers. The vast majority of professionals, recording enthusiasts and home recorders have a computer-centric rig. Computers may be unstable and unreliable, but with the right amount of tweaking and maintenance they can be perfectly stable and reliable. Also, software processing allows for a level of flexibility, scalability and convenience that is unparalleled. Saving and recalling your settings, large memories, huge track counts, and software effects are just a few advantages. That is why people use computers for recording. Having said that, though, there are people with a computer-free setup and are happy with it. If you are not going the computer way, you should know what you are missing out but ultimately it's a personal choice.

Reading through your list of equipment, some of which I have either no knowledge or experience of, I couldn’t help wondering why you acquired it. Some of it you even admit you don’t really know what it is for or how to use it. So why buy it?
I really do not mean to be rude but, I have a small home recording studio/control room and a separate isolation booth and they are crammed with all kinds of equipment, all of which had been purchased over the course of many years. Without exception, every piece of equipment was purchased as a necessity. In other words, as my technical abilities and competence grew, I realised I needed a certain piece of equipment to improve or speed up the recording process.
For instance, I started out with a rather cheap microphone which was good enough, but soon realised I needed a better one. Then I realised I needed a microphone pre-amp and as I became more aware my singing voice wasn’t actually very good, a vocal compressor/processor. I had to learn how to use them, their controls and functions through experimentation and every new song requires changes to control setting. My band mate who shares the vocals (and does it far better than I) requires completely different settings than I would.
What you appear to have done is obtain a load of equipment without the faintest idea what it is for or how to use it.
If I were you, I would go back to basics. Depending on what you want to do, set up the minimum of equipment and through experimentation, trial and error and adding in ancillary equipment bit by bit, learning how to use it, you will gradually grow familiar with the functions and controls.
It takes years to become a competent recording engineer and you cannot circumnavigate the learning process simply buy buying a load of equipment. Anyone can go and buy a guitar, for instance but, you still have to learn to play it.
Sorry if my response isn’t what you wanted to hear but there you go. I nor anyone else cannot give you a lesson on how to use your equipment because most of us only buy stuff when we realise we actually need it. This way we have already been driven to maximise on the equipment we have already, have tweaked it until it cannot be tweaked anymore and then make the decision to purchase either something better, or something to enhance what we already have.
Good luck
MS

Your equipment is extremely limited for "producing others". First of all, the TASCAM only records two tracks at once? It has a limited number of inputs? Depending 'what' of others you want to produce...that may be enough for a demo, if they are also solo artists who want to use, say, samples and stuff with a vocal, or an acoustic guitar/singer. You'll run into a brick wall with band. You'd need at LEAST a mixer, and good real-time mixing skills to record a full band down to only a two-track stereo mix. Remember...once everything is mixed to two tracks (level, pans, EQ's, etc.) you are extremely limited in further processing, and completely limited in further mixing amongst the instruments/vocals.

Computer interfaces and software allow MUCH, MUCH more flexibility in available tracks to record to at once, individual track processing, mixing (levels, EQ's, pans, individual tracks' effects, etc.)

DAWs with good MIDI integration (Cubase, Sonar, etc) also allow you to record MIDI data in from the keyboards, and trigger the keyboards' sounds...AND any other sounds you may have in (or out of) the computer, such as samples (keyboard and software), high-quality soundcards, outboard sound modules, etc. You can also do VERY intricate MIDI data manipulation to control all kinds of things in devices...like filters, cross-panning, levels manipulation, modulations and pitch bends and a ton of other stuff, including sending patch changes, etc. You can also copy the data in one MIDI track, and create one or more tracks to play the same performance using a different sample/sound. Maybe you like two snare drums' sounds, but neither is exactly right. Maybe one is snappy and crisp, but lacks body...and another has body, but is dull? Use both, and mix to taste.

You don't even have to commit any MIDI parts to audio until all the "real" audio has been recorded, so that will give you options to, perhaps, find other samples/instruments to fit around the audio better, instead of trying to destructively EQ the crap out of the audio to fit into the MIDI sounds. The MIDI parts will play along just fine, with the DAW audio as master.

It's easy to copy and paste parts...or entire verses, choruses, etc.

While the TASCAM may have some processing (compressors, reverbs, choruses, etc.) it's very likely you could get better-sounding software ones relatively inexpensively...with even more control and features. Heck, there may even be some free ones that will outperform the ol' TASCAM effects?

Track editing and functionality, throughout, will be much, much easier on a computer screen with relatively easy access to many function screens than menu'ing your way through the TASCAM.

You are limiting yourself with your setup. Can you do recordings? Sure. You are limited to how much you can do at once. You are limited to only what the TASCAM offers as far as mixing/effects/etc.

It all depends on what you want to do, and how satisfied you are with limited functionality and effects/mixing choices.

You can squeeze demo material out of that, sure. That's what most people use them for. That, or as handy scratchpads to capture ideas, etc.

Good luck,

Kapt.Krunch