Stack the tableau by matching color instead of alternating, but keep sequences same-suit if you want to drag them as a group. Odds of winning: 35%.

Smokey Solitaire twists the usual Klondike build: instead of alternating colors, you stack the tableau by matching color, a black card on a black card, a red card on a red card. Sequences still have to be same-suit before you can drag them as a group, though, so a mixed-suit run needs breaking up one card at a time. Played with a single deck, it sits at medium difficulty and wins 35% of the time. Skill, not luck, is what tips that number.
If the same-color build appeals to you, Whitehead Solitaire is the classic version of this idea, and Agnes Sorel Solitaire is another same-color relative. Or try original Solitaire for the standard alternating-color rules.
If you run into anything odd or have an idea that would make the game better, please contact me.
Enjoy the game!
4 foundation piles: Build up in suit from Ace to King, 13 cards per pile.
7 tableau piles: Build down by matching color, not alternating. A sequence can only be moved as a group if it's all one suit. Only Kings can fill an empty column. To begin the game, one card is dealt to the first pile, two cards to the second, and so on. The top card is shown.
Stock: Click to flip over 1 card at a time. There are two redeals, for three passes in total.
Waste: Top card available for play on the foundations or tableau.