And that's exactly the issue: Not in my case!
Please note my sentence: You only have to "wait" a few seconds to restart it,
especially if you use the Navdata API. Do you mean in your case it always takes much longer, even if you DO use the Navdata ?
Because, NOT using the Navdata API will surely result in a slower start, because it will need to load the airport cache and check for any possible changes to decide if it requires being regenerated, and this might take longer, depending how many sceneries you have installed.
And, in this case, if you try to Restart *before* the airport cache has been loaded, it might let you think you need a 2nd restart, when in fact you only had to wait a bit longer. And no, since the airport cache is loaded in a separate thread, it's not always certain the cache is really ready just because the tooltip over the Couatl icon says so, the reasons are complex to explain and are related to how the tray bar notification are works, but it's the way it is.
However, when you DO use the Navdata API, the startup shouldn't take more than a few seconds, since no Community folder is read, no airport cache is used, it just starts and connects to the sim, waiting for Simconnect to reply with the data about the airport.