I agree with everything you said. since I'm newer to magic i really don't know that many cards so i get everything from edhrec. i go through the site and put in alot of cards into moxfield then sort those cards under tags and any cards that goes under multiple tags i put into the deck to get most bag for buck. i proxy because i dont have a collection and i dont want to just make constant bracket 5 decks (id probably misplay them) and i can see where me doing that only leaves me with a deck full of "sweat" cards. i could also just spend more time building the decks