Well, not really problems but certainly annoyances for me! I'm just wondering about the following, if it is to be expected.
Rolo is 4 months and 3.8 lbs. He is so active. We have him fenced into the kitchen just in case of accident. We started out with a small space in the kitchen and as his reliability on the pee pad grew, so did his space. He now has free reign of about 200 sq. ft which is our entire kitchen, his pee pad, crate, bed, toys, food & water, etc.
1. About 70% of the time he pees on his pee pad (well sort of) and the other 30% he pees either in the middle of the floor or right beside the fence to the rest of the house. Just tonight, I was playing with him in the kitchen. He ran over to the 'fence' - as he often does when we play - out of my sight and pee'd. Why is he inconsistent with his pee pad? Also, it seems like he stands on his pee pad and hangs his but over the edge and pees/poops on the floor. I used to call this a 'hit' when he was younger but I'd sure like him to get his hits better.
I would make a larger square with four pee pads to give him more space for now, until he gets use to knowing that he has to pee on a pad. I would also put one at the gate...to let him know that in the house he can ONLY pee on a pad. Later when he's older you can conditioner him to use one pad and location. Right now you want him to go on a pad.
2. He is very active and if I am in the kitchen working, he is constantly biting at my toes. He can get ahold of my big toe in his teeth and yowch!! I can sternly tell him NO, he will stop, look up at me, wait until I go back to work and then start with my toe again. This could go on for 8 or 10 times until I get frustrated and leave the room.
I would clap my hands and say "no bite" looking at him with the mommy look 
and then buy him a bunch of toys to play with and some Bully sticks to chew on.
3. If I get on the floor to play, he constantly wants to chew on my fingers. Same idea as the toe thing. He isn't teething right now. Baby teeth are all in. Seems more like a habit at this point.
Buy him some Bully sticks. They are a finger saver 
Help. Is this 'normal' behavior or am I too slack in training?