Is it a given? No. But it is the plan. Essentially, home audio speakers are supposed to sound good. Monitors are supposed to tell the truth. It's like the difference between an airbrushed supermodel and what she looks like when she wakes up in the morning with a hangover. Gecko is essentially correct. You can learn to use any really good speakers as monitors, once you know what to expect from them. And you can call mediocre speakers "monitors", but they'll still be mediocre. Of course it's your call. Regarding the electric, it sounds to me like you are talking more about wicked clean sound than the overdriven metallic stuff most of the boys here are looking for, which usually means valves. When I want that sound, I plug a solid body into
a Behringer Vamp II modeler set for really clean, and put a mic on
the solid body (no kidding) to pick up some pick noise. I start with the modeled clean sound, and then start adding the mic until I can't tell if it's acoustic or electric. I also use jazz strings, 0.11's, with a wound G, so I get that full chord stuff that doesn't work on most electrics the way they are set up. That's just a weird tip.
You're on the right track. Monitor speakers are simply a killer that we all need, and unfortunately, I haven't heard any with drivers smaller than 8" that I like. 5" drivers can work, but are usually better with a subwoofer. Once you pay for the sub, you realize you should have just gotten 8" drivers in the first place. Don't worry. Whatever decision you make will be the right one for right now. My advice is- anytime you're not sure, don't buy anything. This is a process, and before you are done, you may have purchased the equivalent of a new car. At this point, I've bought a new BMW. Right now, you're asking whether you should buy the steering wheel, or the tires.
Frankly, I'd find out what it would cost to get Armistice to ship you his speakers, and then start playing cheap new and used solid bodies. My best advice on that is to play them plugged into *nothing*. A solid body is a plank with pickups, and yeah the material affects the electrified tone somewhat, whether the body is chambered, etc., but most of the sound comes from the pickups. If you find a solid body that feels good to you, and has a good straight neck and good intonation, you can put whatever pickups you like into it later. I've got an old Korean-made Samick
Epiphone Les Paul like that, that I dropped a pair of
Classic 57 humbuckers into. Yeah, the pickups cost me more than the guitar, but in the end, I spent about $800 on an axe that would have cost me $2500 to buy the pre-assembled equivalent. Find an electric that feels and sounds good when it's not plugged in, and upgrade the sound later. Good luck.