Here's a bit of unsolicited advice for when you play Donkey Kong: Tropical Freeze: Make sure you bring a friend. In addition to being much less frustrating than the standard single-player, the co-op is strikingly well-designed for a 2D platformer. Unless you're looking for a challenge, I feel like it really is the best way to play Donkey Kong Country.
I bring this up mainly for the benefit of those who never got around to play Donkey Kong Country Returns on the Wii, which first introduced the current two-player mechanics to the series. Then, as now, it was a simple idea, but also a really smart one. Playing as one of Donkey Kong's friends, the second player can either tackle obstacles directly with DK or hop onto his back and shoot projectiles that stun enemies. In essence, it builds on the notion of being able to tug along a second player in a balloon -- a feature first introduced in New Super Mario Bros. and refined in Rayman: Origins -- and greatly improves upon it. The second player is still invulnerable, leaving the more skilled player to handle the obstacles, but they can still take part in the action -- even if they're only really shooting peanuts. It's passive, but it doesn't feel passive.
It's not just for beginners either. I've been playing platforms since the dawn of the NES, but I was surprised by how often I found myself retreating to the safety of DK's back. Sometimes it was because the screen was loaded with enemies; but there were other times when the PR person playing as DK just knew the area better than I did, so it was better to let him handle it himself. The drawback, of course, is that it puts more pressure on Player 1 to survive, because one ill-timed jump will result in the loss of two lives instead of one. But then, experienced players should relish that sort of challenge.
The benefits of two-player co-op are most apparent during the lengthy boss battles, which are extremely difficult when playing alone. Playing through them, they almost felt like a reaction to all the crummy palette-swapped hamster battles of the original Donkey Kong Country, where the boss battles weren't much more than an afterthought. In Tropical Freeze, the second level boss alone -- a killer owl -- is a three stage battle with a wide variety of attacks to avoid. It will bomb you with eggs, shoot feathers at you, and try to blow you off the stage with a wind attack from its wings; and the only way to hurt it is to chuck its own young back at it. It's long, complicated, and most of all, unforgiving. Mess up and lose your CPU companion, and you'll be down to two hearts, which can be wiped out in relatively short order.
The boss battles were what ended up being the biggest bottleneck in my four hours or so with Tropical Freeze. Once I got a second player into the mix, though, they became much more manageable. If I screwed up, DK could quickly revive me, just as long as we both didn't die at the same time. That wrinkle would prove a godsend against the ninja monkey that ruled Level 3 -- a simian that could make copies of itself and launch multiple attacks at once. With two of us on the screen at once, we were able to divide and conquer, making it much easier to avoid attacks and retaliate. And if one of us accidentally died, we would get what amounted to a mulligan and be permitted to continue.
That the boss battles are so much easier with two people mostly seems to be an issue of balance; for instance; single-player boss fights would be a bit less frustrating if a barrel were available to recover a companion lost early in the fight. However, these balance issues don't detract from just how fun it is to play with a second player. Going back to the original game, Donkey Country has always been more fun with two characters on the screen at once; and in Tropical Freeze, Diddy, Dixie, and Cranky all add their own wrinkles to DK's traditional moveset, whether by hovering with their helicopter ponytail or pogo-ing around the stage like Scrooge McDuck. Since the platforming in Tropical Freeze is all about managing momentum, it really helps to have Diddy or Dixie to slow things down a bit; without them, DK feels tremendously limited. Playing with a friend ensures that they are always available.
I say all this as someone who's never really bought into the notion that "everything is better with co-op." For the most part, I find playing with other people to be distracting; Tropical Freeze, however, seems to be the exception. Once I had a second player with me, everything seemed to click together. It was still a challenging platformer -- we actually got multiple game overs -- but with a second player it became much easier to enjoy the gorgeous scenery (Tropical Freeze is a lovely game to look at) and the creative level design. It's not absolutely essential for enjoying Tropical Freeze, but it sure helps. One way or another, you won't regret it.