Look, I understand why Funcom makes Yalmahas rare and expensive. For one thing, it takes a lot of challenge out of the game to fly over every hostile. For another, you don't get to see all their pretty scenery. In fact, seen from the air, this game frequently looks like crap.
But because the ground vehicles suck so badly, the only real alternative is to jog - which gets really boring, really quick. In theory, for those kinds of distances, you could drive. But nobody does. The reason nobody does is that it doesn't actually get you there any quicker. By the time you spend the IP to raise Vehicle - Ground, you could pour those same IP into Running. That would get you the same trivial increase in speed, and it would work in missions, too. So that's what everybody does.
Which is stupid. Ground vehicles need to have two speeds. The "walk" speed should be about the current "run" speed. The "run" speed should be about half the speed of a Yalmaha in flight, or roughly the speed of a Yal on the ground. That would make them worth using.
For bonus points, to make them even more popular, they need to make two changes to the graphics. Trivial one: the Mid looks silly enough at its tiny size without making it look sillier by putting it at ground height. There's nothing in the game universe's logic that keeps it from flying at head height, and it would look less silly doing so.
But that's trivial and unimportant, because the Mid is such a specialized vehicle. No, the Kodaik is the default ground vehicle. It's affordable. Its requirements are not unreasonable. It's too slow, as mentioned above. But it would be even more popular if it weren't so ugly.
For one thing, it's too small. You could almost convince yourself it was a hoverbike with an enclosed canopy - if it were about half again the size it is now. It could also stand to be noisier.
But with a bit of work, the art department could also make it much, much cooler. Early on, the banner ads for this game showed a woman astride a hoverbike. That's what the Kodaik needs to be. Change the mesh (and texture) for the bottom half of the character to a hover-cycle -- include heavy wrap-around leg guards, so you don't have to match the leg size, shape, and armor. Fix the character posture at leaning slightly forward holding the handlebars. (I don't know what to do with the weapon. Drop it from the icon would be the easiest thing to do.)
Bet you money that people would stop whining about how expensive it is to fly, if they could zip around the outside areas at twice their current speed and look stylin' doing it.