I am debating on playing a Brawler and a Slayer and was wondering best way to build either one. I am interested in feats and ability scores. The Brawler I plan on doing unarmed strike and slayer doing TWF.
Brawlers do lower damage with UAS than with weapons. I would really suggest a Cestus on the Brawler instead for better crit range and dmg dice scaling.
Slayer is great for 2wf and combat style will let you get 2 wpn rend early, which is the best 2 wpn feat btw, while bypassing pre-reqs.
Well, if you go unarmed as a brawler, the most common suggestion would be to grab pummeling style and pummeling charge.
Pummeling style lets you pool all the damage from your full attack into a single attack. This lets you deal with DR only once per full attack, thus DR/20 is like DR/3 when you have 7 attacks. That solves one of the major problems with unarmed builds (it also means you can possibly skip the amulet of might fists in favor of spells like greater magic weapon or greater magic fang since those enhance you attacks, and their only flaw is that they do nothing for DR besides magic).
It also lets you crit with that pooled damage if any of your attacks threaten a crit (it is confirmed with your highest BAB, so even the BAB-15 hit can change things up). I means that the more attacks you have, the more likely you will be to crit with your full attack's damage. Eventually, you are on par or above high crit weapons on average.
Pummeling Charge lets you do the pooled attack at the end of a charge. That is basically pounce. Thus, you get a ton of full attacks.
Pummeling style needs monk or brawler 2 (or BAB +6 for other classes) and pummeling charge needs monk or brawler 8 (or BAB +12 for other classes).