Burn
As Squee_Spirit_Guide pointed out on his list, Jaddi Offshoot is a good outlet to keep yourself present on the board. Protective spells like Shell Shield are gonna be crucial in these matches and maybe Blue Elemental Blast, and to that end Hydroblast. (10/10) recommend having somewhere between 2/2 --> 3/3 in your mainboard/sideboard set up, due to how powerful that match up and game can be.
Graveyard/Reanimator
Honestly if you got budget like that Leyline of the Void will shut that shit down real real fast. Otherwise, a Grafdigger's Cage or Tormod's Crypt is likely gonna be enough. The issue with this match up is your function (The milling) works against you, so it's even more paramount to have responses lined up: Stifle, or even Trickbind would be helpful in keeping some of the activated effects at bay.. hell, even Disallow exists. In this scenario, I'd recommend something like Baral, Chief of Compliance to help keep your hand stocked with the cards you need, because you'll spend a lot of time stopping your opponents plays anyways.
Stompy
You prolly die, tbh. Not too many big bois to help this situation other than keeping some consistent disruption available, with Counterspell, Vapor Snag, Aether Gust, etc. I mean Charix, the Raging Isle is an on brand solution that provides a big boi, but it's kinda one-dimensional. You're not really gonna use him for anything else other than eating a massive swing from the opposition.