It's a lot more setup but I've had a good experience with redux, redux-persist and localForage. localForage picks the best available browser storage API. One can select which subset of data to persist with redux-persist. It does assume a redux buy in...
Unfortunately, the CALF series have been notorious for having problems or causing crashes in the past. If you do want to try it out, I highly recommend getting the latest version or building from git as a lot of distributions package an older version in their repositories.
Things are slowly getting better if you want to run Windows VSTs under Linux. I found this very interesting as a overview of some of the current possibilities: https://www.youtube.com/watch?v=jsZnSg4DKDU
It is a demonstration for a proprietary DAW, Bitwig, but he does talk a lot about Windows plugins under Linux that I imagine applies to Ardour as well.
If you follow the "Ready-to-Run Program" prompts on the official download page[1] as an anonymous or unsubscribed user, you will reach a page that explains their method/philosophy.
I'm sure Paul would be happy to speak to you on IRC (#ardour on Freenode) about successes/failures but of course I can't say this for sure.
Also, I am awaiting a stream of Paul's upcoming talk (as I can't get to France for LAC2017[2]) "20 years of Open Source Audio: Success, Failure and The In-Between"[3]. I hope part of the talk will address the financial aspects that are of interest to you.
I've recently adopted a similar approach. I have a virtual machine running the same OS and version as the target production machine. I'm using QEMU and connecting to it via ssh.
There are a number of exciting projects in the Linux audio that may be of interest here. I'll just name a few, in no particular order, that have tickled my interest.
That seems like an interesting avenue to peruse. I would imagine you would end up reimplementing a lot of what Calc has already solved. I'm thinking about mapping cells to cell references (A1:C57), how to handle VLOOKUP, sheets etc. If I had to do this, my approach would probably be to take the headless Calc code and strip out the parts that are unnecessary.
There seems to be at least one tool that can convert macros from Excel to Calc for you: http://www.business-spreadsheets.com/vba2oo.asp
Having done no testing, I have no idea how well this will work.
I don't quite follow your question but I'll give it a shot. Here is a high level version of how I am currently using the tool: A user is presented with a bunch of input variables on a web page that are then set by the user. These variables are sent to the server and the server sets the relevant cells using spreadsheet_server. Resultant values from other cells are retrieved by spreadsheet_server and then sent back to the web page and presented to the user in the form of a graph or table etc.
Pretty much all of the logic to get from input to output is handled in the spreadsheet by LibreOffice.
I probably need to be more descriptive. The locking is just within Python to prevent simultaneous reads and writes to the spreadsheet messing with expected results. This makes sense for my use case but probably not all use cases.
Currently it simply check for any new spreadsheet(s) in the ./spreadsheets directory and opens them in LO Calc. Any spreadsheet that has been removed will be closed in LO Calc. There currently is not support for what you described. There is potential for that sort of thing to be implemented though...
I've been using it for a fairly specific use case: Creating web applications from business logic that has already implemented in a spreadsheet. So instead of trying to figure out what the spreadsheet is doing (they can get fairly complex and the flow of calculation can be difficult to follow) I just treat it as a black box. Input some values here and read the resultant values from somewhere else. Integration with flask/django and you have a prototype within a day.
I wrote some plugins for fun a few years ago in Lua: https://github.com/robsco-git/ardour-plugins
My understanding is that the plugins one writes for Reaper are compiled on the fly so I imagine they offer better performance.