I find combo edge pocketknives somewhat at a disadvantage vs. dedicated fine edge or serrated ones. You can't go wrong with a plain edge on the type of knife you are interested in.
You are correct. It is easier to sharpen a plain edge knife. But it is really not that difficult to sharpen other types of blades with the right kind of sharpening tools.
For cutting branches, a dedicated saw is what you need. If you want to use blunt force to chop wood, make sure the steel is hard enough to handle the duty. Leaf spring is very good when forged correctly to form a larger knife like a bolo or machete or even sword or ax. The type of alloy is very tough and can resist wear better than high carbon filled steel.
If you are just buying a knife for novelty, it doesn't matter if the blade is serrated, plain or both. If you are prepper like me, I suggest you look at multi-tools with a very good quality steel knife. In a way, you have other tools available to you to performing specific tasks.
Boker Plus Keycom knife has caught your attention. Boker is a reputable knife maker. The model you are looking at is very small. The blade length, I would say is just about 1.5 inches. To consider one that has combo edge on this size is not only impractical but also laughable. One good thing about this Boker keychain knife is the blade quality. It uses AUS-8. Same steel used by other high value knife makers like Spyderco, Kershaw, Ontario, etc.
I have collected a lot of blades through many years. The most I use is the one I carry on my keychain, a victorinox classic stayglow model. And for everyday cutting task at home, I use either a beater Husky box cutter or a Gerber EAB pocket knife. I like the idea of replaceable blades. This saves my high value knives from dulling.
If you are interested to see my modest collection, just holler out
