I use the Jetboil PCS a lot (same as Flash, without the little glow-panels to tell me when it's hot), and dump my freeze-dried meal into the pot to rehydrate (the neoprene sleeve keeps the food hot until it's ready to eat; pouring water into the bag lets it cool down too much, and I don't use a cozy.)

The system is heavy, by some standards; a Pocket Rocket and Titanium Kettle will weigh half a pound less. But, the Jetboil is convenient, and more fuel efficient. The efficiency comes into play on longer trips: last time I was out for a week, I took only one Jetboil cylinder; previously, I'd need a second cylinder for the Pocket Rocket setup I used - and the extra cylinder weighed half a pound, using up my weight savings.

Again, it all comes down to what works best for you, not a purely objective comparison of weight. I find myself reaching more and more often for the Jetboil, just because I like how it works in the field. It's a good system (it's really hard to find a bad stove nowadays), so there's no reason to reject it out of hand. The Group system is probably overkill for the solo cooking you describe - but would be a contender if you intend to go in a group and take only one stove.

You mentioned sharing the tent; if it's just you and one other person, buy a Companion Cup for the other person. You'd have to take turns cooking, but if that second person doesn't always go, you could leave the second cup behind. If you're both pouring water into a bag, you might not even need the second cup - though it might be handy. You can boil 24 ounces of water in the Jetboil cup, even if that fills it above the recommended fill line. I've found that the recommended fill line seems to be oriented toward actually cooking - fill it above the line with, say, a Lipton/Knorr side dish that has to be boiled, and you'll probably boil over. But fill it above the line with water only, and it will never boil hard enough to boil over.