One of the better options for a self-discard deck in blue and red is Rielle, the Everwise
Vega, the Watcher is a fantastic commander for anyone looking for a different way to gain value for casting spells in unusual ways
We have plenty of ramp and ways to interact meaningfully with the board
seven abilities and 7/7 size our second highest scoring card
If only one of the targets is legal when Fight for the Throne tries to resolve, the creatures won't fight
In your draw step you can draw, for free, two more cards and then place two cards you've drawn on your deck in any order, so it's like a free Sensei's Divining Top, and if you replace those draws with something like Abundance then you'll not have anything to put back so you get all three effects