It's really a matter of TRAINING and limit-setting. If you allow (or encourage) the dog to become an appendage, many of them will. Yes, they are companion dogs, and like being with their "peeps", but they don't HAVE to be joined with you at the hip.
I don't really mind that Kodi follows me into the bathroom, so I have never trained him to stay out. Other people choose to teach them that they must respect that space. As far as the kitchen is concerned, we have a big, eat-in kitchen, and a lot of family-time takes place there. I don't want to make Kodi stay out of that room. But, like you, I cook, and I drop things. So teaching "Leave it!" was high on my priority list when he was a puppy. I can drop a whole cutting board full of onions on the floor (yes, I've done this
) and he will stand back and wait when I tell him to. OTOH, if I drop something he CAN eat, I'll tell him "Get that!" and he's on it in a split second.
But if YOU choose to teach your dog not to cross the kitchen threshold, you can certainly do that, no baby gate require. (after the puppy phase of course!) My preference s to teach "Place!" or "In your crate!" so that whatever I'm doing, ANYWHERE in the house, if Kodi might be in the way, and a danger to either himself or others, I can send him somewhere I know he's safe.
Havanese are a very, VERY trainable breed. If you get a good one, started right by a good breeder, you should have no trouble molding the behaviors YOU want. If you are talking about adult dogs, I think that Havanese with behavioral "issues" are Havanese that haven't had the training they need.
If you are talking about puppies, Havanese puppies aren't that different from other breeds. Some find that they take a little longer to potty train than large breed dogs, but this doesn't need to be a problem... it's a matter of controlling the environment (not giving them too much freedom, and lots of praise for getting it right) until they are confirmed in good habits. Do the chew and use their needle teeth? Yes, but no more than most breeds, and less than many. Do they bark? again, yes, but most puppies of most breeds go through a "barky" phase. With good handling, management and training, they grow out of all of these things. That's what raising a puppy is all about!