I used to have a Jack Russell Terrier. I got him from Santa when I was two. He lived to be about 15, I believe.
He was
so great and
so protective (not really in a bad way) but really bad at the same time. He used to kill our chickens (god forbid one got loose), rabbits, opossums, etc. He was very hyper. He loved to run outside. I loved him to death and can't imagine not growing up with him but I never get another JRT.
My mom has another one now (that she basically inherited) and he isn't as bad. He loves playing with Britney and Brooklyn and does OK with understanding that they are tiny. He does love to chase rabbits, squirrels, etc. He listens pretty well- not stubborn at all.
ETA: I noticed you mentioned Maltese, Poodles, or Mixes but I didn't noticed that until after I typed/sent this.. oops.