>>19928179I'd consider something from Gen 3 if I were you. I'd love to raise a shiny anything in OR/AS and I'm sure many other people would too.
That 6 IV Modest Melotic you have at level 1 would be perfect for this considering how annoying catching a Feebas is.
The 5 IV Timid Ralts is also a good contender. Black Gardevoir/Gallade look pretty good.
That Mudkip looks great too.