What you have currently is pretty much the same as how many new nav systems would be built. A few things have evolved, e.g. digital radar, but that's not significant in the context you are asking. It's also possible to replace all those 0183 connections with a NMEA 2000 bus, but that can be problematic is the system grows beyond a very basic setup.
The proprietary lock-in points remain the same:
1) Radar overlay on charts is proprietary, so the only way to overlay Raymarine radar is on a Raymarine MFD. The same is true for Furuno, Garmin, Simrad, etc., with a few exceptions.
1a) MaxSea PC software (the same thing now as Nobletech) can overlay Furuno radar. It is still proprietary, but works because MaxSea is in close partnership with Furuno, is half owned by Furuno, and is the software that runs on the NN3D and TZTouch chart plotters. It's all one happy, proprietary family.
1b) Some products have hacked/reverse engineered the Simrad digital radars and can overlay them on charts. I think OpenCPM is one of them, and it might be available as a bootleg feature on Coastal Explorer. But it just overlays the raw radar return. ARPA, for example, doesn't work so you lose that feature.
1c) Some other exceptions exist where there are licensed connections between chart displays and radars. For example, RosePoints ECS product has an optional interface box that links Furuno and a few other radars to RosePoint ECS. But that's outside the scope of what most or all of us use.
2) Another proprietary lock-in point is control of radars and autopilots from the MFD. Things like changing the radar range, operating EBLs or VRMs, acquiring ARPA targets, setting gain and rain rejection, can only be done between same-vendor products. Similarly, autopilot configuration, tuning, enabling and disabling, and other advanced features can only be done between same-vendor products. But this DOES NOT include having an auto pilot follow a route on a chart plotter. That's done using standard communications and in my experience any pilot can follow a route on any chart plotter.
3) The other proprietary lock-in point is the display of fish finder echo returns. I think these are all same-vendor only, and I don't know of any exceptions. Simply the depth is conveyed via a standard interface and can be displayed by anyone, but the more detailed echo return that maps the water column is proprietary.
That said, there are still some very satisfactory ways (in my opinion) to integrate different vendor and/or dedicated devices. I recently did a
blog post on how to integrate a dedicated radar with Coastal Explorer so that radar ARPA targets are mapped on Coastal Explorer. It's all done using standard interfaces.
I personally struggled with the whole question of single-vendor, proprietary, integrated system vs multi-vendor, standard interfacing, dedicated instruments. Here's another blog entry of my
confused musings on the subject .
The fundamental problem with the single-vendor integrated systems is that it's all or nothing, and the whole system is only as good as it's worst component. And because it's all or nothing, you are very likely to tolerate and suffer through the worst component because you can't replace it without replacing everything. On our trawler I ended up with dedicated devices, integrated using standard interfaces, and couldn't be happier. But we also have a small open boat and on that I'm doing a small, integrated system. So one answer doesn't fit all.
