A couple of points...
-VHF Marine is the right tool for the job. This is what it's designed to do. The change in the rules that permits use ashore a few years ago just legalized what most were doing already.
A portable radio with a decent antenna at your home will do a lot.
-No single radio service is going to cover absolutely every situation. Multiple forms of communications would be a good idea. Chances are you already have a cell phone. While coverage on the lake may not be perfect, chances are there's some, and calling your wife, friend, 911, etc. are all options. Get a waterproof box to keep it safe on your kayak.
-If getting help in a true emergency is one of the desired options, then this is where a Personal Locator Beacon comes in. That is -exactly- what they are designed for. Hobbyists will come up with all kinds of reason why they don't want to use those, and they are all B.S. A PLB will run you about $200 and will get you help nearly anywhere on the planet. Again, this is one of the "right tool for the job" items.
-Amateur radio is a good option, but as for relying on it in an emergency...
There is no guarantee that anyone will be listening. It is a hobby service. There is no requirements that anyone be listening to any specific frequency at any specific time. Yes, there are often people out there to talk to, but it is NOT an emergency radio service and should NOT be relied upon to get help in an emergency.
-You will -never- have 100% radio coverage. Ever. You can spend thousands of dollars on equipment, repeaters, etc. but nothing is going to work everywhere every time. A PLB is about as close as you can get.
-GMRS is often overlooked, but it is only as good as the system you build. Because of PL/DPL tones, there is no guarantee that anyone else will hear you.
-You should not base anything off your wife getting her amateur radio license. If she doesn't want to, don't force her. I was fortunate in that my wife got hers. It's handy, but I do not expect her to be sitting by the radio 24x7 waiting for my call. That's why we have cell phones.
-Radios are only useful if there is someone listening on the other end. No amount of radios, technology, repeaters, etc. is going to mean squat if there is not someone on the other end. There will always be someone answering 911. PLB/EPRIBS will always get a response.
-Relying on a radio as your only safety net in an emergency is never a good idea. Radios do not replace being prepared, having the right skills, or having the tools to get you out of a bad situation. A radio should be one of the tools in your toolbox. Not your only tool.