In addition to what @true blood suggested, you'll need to start joining boss fights with good rewards. They can be gotten in large quantities(with goods stats as well) easily than any other means. You're already on the right track with your skill points allocation. It is all about finding the right balance between leveling and strength. The higher your leveling rate, the better your chances of getting stronger. Hence I'll suggest that you use your skill points this way;for every 20 sp, add +5 stamina, +5 health, +5 attack.
When your stamina gets to 1500, adjust to; for every 25 sp, add +5 stamina, +5 health & +10 attack. Later on when stamina gets to 2500, you may change to +5 stamina, +5 health, +10 defense & +5 attack for every 30 skill points you get. You may make some adjustments along the line by sharing some parts of the attack with defense instead of all out attack. It all depends on you and how you want your character to be but don't ignore your stamina, health & boss fights since you want to win those on your fight list.
As for boss fights, the best/easier way to get those with good rewards is by joining a syndicate/group whose members have unlocked those bosses and they share theirs among themselves. When attacking these bosses, aim for minimum damage required to be rewarded then move on to others unless you come across those with good xp return and you have the stamina. Remember its all about getting the right balance between xp/leveling and strength. Same applies for attack and defense. Worry about attack first then later on defense because revenge is sweet.
Last edited: Mar 26, 2014