So I've been thinking about this.
I feel at least one more Donkey Kong character is inevitable. DK is the 5th best selling Nintendo series. It's only behind Mario, Pokemon, the Wii series, and Zelda. Donkey Kong Coutry also got a revival between Brawl and Smash 4. Not to mention Fire Emblem got four characters, and that is nowhere near as popular or well known as DK. There's also been a suspicious lack of DK stages. There's a lot of speculation they're saving one for a character reveal. So yeah, I think we're definitely gonna get a new DK character. But who?
I feel it's between Dixie and K. Rool. Both have several things going for them. Dixie was recently revived in Tropical Freeze and is female. As we know, there's been a lot more emphasis on female characters this time around. But while I have no doubt she could be unique, she seems like a likely choice for a semi-clone. K. Rool is the main villain and could take over the slow, lumbering powerhouse archetype that Bowser no longer is. Unfortunately, he hasn't been in a major DK game for some time. I want K. Rool more, but Dixie is more likely.
Or we could get both.