The system needs to be programmed to shuffle a magic deck as a player would, separating land and non-land cards, shuffling them separately, then combining them into a single deck. I constantly get mostly land and no playable cards, or all playable cards and no land, or only my high mana cost cards and a few lands, or only low mana cost cards and nothing but land after that. The ratios are perfect, so there is literally no reason statistically or logically that this should be happening as often as it does. I have had games where I literally had to mulligan all seven times just to get something playable, which, of course, meant I got nothing playable and conceded.