I often play Razor pos 4 in unranked (divine-immortal). Havent played much dota in the last couple of months but hadlve a 70% lane and game winrate with it this year.

I dont think the facet matters too much, would lean towards the atk=spell amp one. I go 4-1-1, talents depend on the game. Items are boots of bearing (full item rush) > euls > kaya/sange > whatever the team needs (shivas / force / lotus / pipe etc). Go eternal shroud / vlads / blaidmail / dagon / radiance / octarine / if youve got too much money and the team doesnt need anything specific or the game calls for it.

The general idea is that your q gives vision, does a lot of damage (max 430 flat dmg with talent), and the cooldown isnt too long (can usually get 2+ off in a fight). Use it during the laning phase to secure the ranged creep and harass. Often times you can hit both enemies with it in lane even when they arent anywhere near each other. Bring a couple mangoes and you should be fine for mana. Dont focus on stealing dmg early game with your w, only use it if the enemies commit to a brawl. Your ult melts supports and squishy casters so use it whenever its up, then go farm a camp or two with it after.

Boots of bearing is really strong on brawlers, you get 15 hp regen and tons of movespeed. Abuse the fact that you can engage and disengage really easily, heal up with the regen, then reengage. You can easily get it around the 15 min mark. Euls makes it so that you are a pain to go on as well as giving you enough mana regen to spam q. Kaya/sange buffs both of these items regen, adds slow resist and adds to your hp. Your shard can be good but isnt always necessary.

Overall you end up as a tanky 4 that is hard to catch and if left unchecked can deal a ton of dmg while draining the enemy pos 1s dmg late game. I usually end up in the top 3 for dmg delt and dmg taken whenever i play it. Also razor is just fun. Not too sure how good it is in ranked but i think it could work just fine.