Thoughts : you don't have any lifesteal, frozen mallet is kinda meh on Trynd as the Q heal is less efficient as it's flat health not %missing health, you're better off with resistances. The permaslow helps for sure, but eh.. kinda situational imo.
You don't have waveclear items. Usually Trynd mains go for either statikk or hydra just to have an easy fast hardpush for efficient splitpushing. You're Trynd so your waveclear isn't terrible either but getting a waveclear item is quite strong.
TLDR : no lifesteal, no waveclear, too much health?
Good points: CDR is really good, very high mobility, strong damage output and duelling. Reaver's mana gain is useless but you don't really care. High elo players such as Boxerpete use it on a regular basis.
I'd probably swap FM for botrk, and PD for statikk ; which makes a very offensive build.
Situationally, I'd swap ghostblade for
or
if tanky enemy team, or potentially a defensive item (with resistances most likely :
(don't use the active, just take for 80 armor + MR in teamfights) ?)