Streets of Rogue is EASILY my favorite game of the last few years and I don't expect that to change until the sequel drops.
The emergent gameplay is spectacular and allows for an incredibly variance and freedom of playstyles. Toward that end, Madguy made sure to include the character and map making options.
No run is ever dissatisfying, samey, or boring. If you disagree and find yourself bored; try modifiers to spice it up!
All in all, this game is a GEM.