On Amazon, you don't have many options for frenzy charge generation. If you're sticking to Amazon then what you're doing make sense for mapping = armour break for endurance charges and Resonance to convert to frency (do you have enough physical dmg for armour break?). For bossing, I would use Primal Strikes with with Voltaic Mark or Thunderstom. You could also try Spear of Solaris - LightsWoorld released a video 2 days ago using SoS for bossing. Also worth noting in this video, BM Ascedancy is utilised for charge generation during mapping.
Other way to generate charges, probably most reliable but requires most investment, is through Ritualist where you take the Ascendancy node that lets you activate charms with mana even if they don't have charges and slap on 2/3 Valako's Roar. MisoxShiru has a good guide. Although this build requires legendary helm and body armour so reverse chill might not be an option for you.
My recommendation is using DeadEye. It's personally what I use: LS for mapping and for bossing I switch between Glacial Lance or Explosive Spear. My frenzy charge generation comes from called shots (automated application of Sniper's Mark) and i take chance to get extra frenzy charge from Ascendancy and from Weapon so I have 100% to gain extra frenzy charge (110% if we count the rest of Passive Tree). I get extra speediness from Tailwind (Ascendancy) and i take the MS nodes on the tree. If i move around my tree I could get extra 8-14% MS. My build isn't using reverse chill, but it could.
Here is my poe ninja : LINK