I edited my last post to reflect the order your pics were posted. It further illustrates the skill level you are using in dialing in your parameters. So the middle is now the last, so to speak.
I so get what you are saying about the two condensing coils. Since the one is air and the other is water, they will find different balance points when you switch between them. According to your last post, it seems the water tank is already running at closer approach temperatures than the air coil. This is indicated by the high head pressure of the air coil at the middle reading. If the water condenser ran at a lower head pressure, it is already more effective than the air condenser.
This doesn't mean you can't improve it. Adding more surface area to the water tank loop will increase your heat transfer. The system will find a balance point with less head pressure. Your amp draw and liquid line temperature will drop accordingly. This is a case of diminishing returns, so at a certain size it becomes uneconomical to add more surface area. It is up to you to decide how big is too big.
The other factor that makes a big difference is the compressor displacement. If you optimize your water loop with this compressor, it won't be big enough to move enough heat at the same level of performance with a larger compressor. The added displacement (and resulting increase in mass flow) would raise the balance point to a higher compression ratio.
The txv in the system will amplify this effect until your evaporator reaches its limit. As you can see, the txv is already trying to feed your air coil more head pressure than you are comfortable with when there is enough refrigerant in the loop. With any compressor, the upper limit on system charge will be found during summer conditions while running the air coil. When the ambient air is close to 100 degF, it is easy to find the critical charge by measuring head pressure and compressor head temperature. Keeping the total charge below this critical charge will prevent overheated oil and overpressure of plumbing.
Once you set this critical charge using the less effective air coil, you can rest assured that the water loop will always be running at a more efficient, less extreme balance point. Depending on how much more effective the water loop actually is, the system will always be saving you compressor amps and run time.
For now, you can simulate these conditions by blocking the airflow of the air coil or enclosing it so the heat it produces is recycled until it gets hot air running through it. At this point, you can adjust the charge and watch what happens to the compressor discharge pt.
Once you get the condenser operating within your level of comfort, I would highly recommend running it like you stole it with all obstructive measures removed. Take lots of readings during this run to establish baseline operating conditions (subcooling and liquid line temps, refrigerant and air dT, condensing pressure, amp draw, etc.) over a range of indoor temperatures. Then switch to the water loop and jot down readings once the system finds its balance.
This sounds like a long and drawn out process, but it isn't as difficult as it seems. It is a short and sweet version of what design teams do during early prototyping of concept systems. Having baseline measurements and establishing upper limit conditions is super valuable. If some plumbing leaks or pops, you can look at this data to set your charge after a repair. If you change part of the system, you can use the parts that did not change for comparison. When seasons change, something good or bad may happen. If you don't have log data to look at, you may never realize a change until the electric bill comes.
Sorry for the long posts, but the answers that lie ahead of you are not so simple. From your involvement level , both in this and past projects, and speed at which you are perfecting your knowledge and rigs, I feel it would be cheating you out of doing your best. I can tell all these ramblings are not falling on deaf ears and blind eyes.
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