Try Sheen proc Parrrleys. Once you go Sheen, you never go back.
and upgrade it for a Iceborn Gauntlet
I know it doesn't get you speed, but hey, AoE damage + shiv proc => clear a minions wave in a parley, with bonus gold for every creep ? you're gonna love it.
And your team too, when teamfights come and you deal your damage to every ennemy, slowing em !
Triforce is actually an eventual goal with a speedplank, usually. I think. TT, so far, I've been going boots->shiv->boots of swiftness (game usually ends around here)->zephyr's blade (at which point slows, at least, can screw off. Poor ashe.)->something else, usually starting to build toward tri if it reaches that point. I'm willing to sacrifice a single item slot to sanity (i.e. without movespeed), but not two
Other current thought is to slip a tiamat (or maybe iceborn, sure) in there somewhere, toward the goal of farming like, entire waves with a single parrrley. Adding AoE/multihit
really seems to boost parrrley's effectiveness, honestly. Extra gold aside, potentially turning it into a mana
generator is all kinds of awesome. Wouldn't be a speedplank at that point, but ravenous/iceborn/statikk could make for shenanigans. Ridiculously expensive shenanigans, but still. Do think it'd regulate you to a somewhat more support-y role vs. enemy champions, but... that's kinda' okay. GP can do that via the slows (fairly weak, but also very constant) and the E/R. Parrrley'd still hurt like a whatsit and I'm not entirely sure what else a GP needs, ha.