I found the number of skill pints you need to increase a stat is allways 10 + x, where x is the stat without the last number. For example stat 75, youu would need 17 to incease to 76. So you need one PP more per every tenth stat-point.
The needed PP to increase skills are different, depending on the skill you want to train. But yes, it\'s getting more an more expensive the higher a skill or a stat is trained.
Agility is not only increasing you dodging rate, it also inceases how fast you can hit. So if you\'re really really fast, you can do more hits per second.
Hope this helps answering your questions
