First, I know this is complete heresy to the "connected", but I encourage you to really think critically about your "need" for high speed Internet access and all the rest. I know you are used to having it, and I know you think you need it because most cruisers used to think they needed it, but I believe that if you really think through the things that you do everyday you might find that it is much less of a need than it is a desire. Yes, I know you like to sit and browse the web at high speed, see your email come in the instant it was sent to you, and all the rest, and it is very easy to justify in your own mind because you're used to it, it is an easy thing to get used to, anyone who is online thinks they need high speed access 24/7 who has had it for any length of time, the same as they think they need a cellular telephone after having one for any length of time. But do you need that, really ?
The reason I mention this is because you may not be aware of it but there are ways to live very far afield if you can think critically about what it is you are doing and trying to do. It is easy (and lazy) to just assume that you need bazillabits of speed, when what you might really need is a server run by someone else attached to a high speed link, access to your email a few times a day instead of constantly, fax access a few times a month instead of every minute of the day like you imagine, snail mail delivered weekly instead of daily, etc. Most people don't really want to take the time to think critically about it, it is easier to just say you need high speed access all the time, just like saying you need your own washer/drier is easier than planning trips to the laundromat, or saying you need your own [insert tool] instead of just renting or borrowing it occasionally. If you can think in more detail about what it is you actually need access for you might find you suddenly have a whole lot more options available to you.
One example is email. You are probably used to having your email light up in an instant whenever something comes in, and you probably think you need that to happen to be responsive in a reasonable amount of time, but do you, really ? Yes, there are very rare occasions in most people's lives when a few minutes might make a difference, but how often does that really happen ? Most people can actually read their email a few times a day, or even just twice a day, or once a day, and if you can get down to reading your email once a day suddenly all kinds of options open up for you that you may not have thought about. If you can read and respond to email just once a day with periods of higher activity at times when you are in a marina, for example, then you can start using HF radio and commercial service providers and Pactor modems to send receive emails most of the time, and that means you can essentially be anywhere on the earth because the range of those communications mechanisms are very far, much further than any kind of cellular style access or even satellite based access which sometimes has dark spots around the globe. Suddenly, just by changing your own mind about what you "need", you have opened up a lot more possibilities.
The same thing is true of almost everything you are considering. Another simple example would be a printer, a laser printer, you probably assume you need that all the time, that it always has to be up so that you can print just by clicking a button. But is that really true ? If so then you need constant A/C power and need to be hooked to a dock, probably, because laser printers use a lot of electricity even when they are not printing. But what if you could just reach over and turn the printer on and allow it to warm up whenever you needed to use it, then suddenly you don't need to be connected to A/C power all the time, you can use solar panels, wind generators, etc, because the load isn't constant it is only when you need it. What if you take that one step further and realize that the only time you usually need to print something on a laser is when you are sending it via snail mail, etc, and then you might realize that you don't need a laser printer on your boat at all, what you need is access to a laser printer at the physical location where you typically mail things, or that you need a laser printer on shore somewhere, etc. Maybe you eventually realize you don't even need that, that you can turn things into PDF's and email them instead of printing them, doing away with the laser printer altogether.
Everything on a boat can be improved by this process, by being critical, by constantly re-evaluating what it is you are doing, how you are doing it, what your real needs are vs. what is just convenient, etc. You may assume you need a high speed desktop computer so that it is really fast, but do you ? When do you actually need that speed, are you just writing Word documents ? Maybe what you really need is a very slow small computer that can run off of a few watts of power to do your work on a day-to-day basis and then have the desktop sitting around turned off and use it only when you absolutely have to have the speed for working on video editing or something similar. Maybe you don't actually need a fast computer at all.
This all probably sounds very annoying, because when you are used to being online with lots of bandwidth, lots of processing power, etc, you just start to assume it is non-negotiable. But if you can make it negotiable and start opening your mind up to the possibilities you can greatly increase the amount of freedom you have by letting go of just a few of the things that may have solidified themselves into techno-dogma in your mind.
I am writing all of this because you seem open to examining your own motivations about technology and convenience as evidenced by your approach to transportation in your original post, many cruisers can't give up the car, but you seem open to the idea. This all assumes you are even interested in cruising instead of simply living aboard at a marina. I just throw all of this out there as something to think about, maybe you don't need high speed connections and all the other stuff as much as you think you do!