Software for complex thermal plants

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I'm looking for input on which software to use for complex thermal plant simulation. I'm in California and have seen more complex plants recently due to increased use of central HP water heaters doe to all-electric building requirements. These plants often involve heat recovery chillers and thermal storage and therefore have more complex connections between the HHW, CCW and CHW systems than is typical. Methods of modelling i've tried so far are:

• IES - note really up to the task, thermal plants are pre-packaged and don't allow for much customization
• TRNSYS - can definitely do the job but has a steep learning curve and I have struggled to build stable models. I found that I can rarely get reliable results within a reasonable timeline to provide input to the design
• EXCEL - works as a hack but is either a very simplistic model, or a very complex spreadsheet which is prone to errors that are difficult to track down

The ideal software would:

• Include models for heat pump boilers and heat recovery chillers as well as more typical chillers, cooling towers, gas boilers
• Include models for fluid thermal storage tanks, preferably both mixed and stratified but i could live with just one or the other
• Allow the user to define connections between components and controls as needed for the project

I haven't used Open Studio, Eplus or Equest, would any of these be a ebtter fit for me? Any other packages out there I should look into?