Unfortunately, I have to say that those are campaign specific questions.
Assuming a relatively powerful HARP campaign (like my own), with the power heroes (demigods) being around level 20, I would go with -
Town guard - level 2-3, with basic sergeant around 5, and captain around 8-10.
Experienced soldier - minimum level 4, but could go up to 10-12 depending upon how experienced you want to make them.
Elite Warrior - level 12-16
1st level adventurer - trained and knowledgeable, but definitely still a rookie. Just starting out, but able to do some basics.
Basic Competence - 1-4
Professional 5-10
Mastery 11-15
Keep in mind that this assumes the character to heavily focus on their skills.
Most characters will have at least +12 stat bonus in their key skills
Assuming they max on certain skills, they would have 6 ranks at level 1 (+30) for +42. A Medium hard skill attempt is successful 40% of the time.
At level 5 has 18 ranks for approximately +78 total, and then at 11 will be at +98. The diminishing returns really push the focus away from simple skill development and over to talents and professional abilities to develop that expertise.
I hope that helps.