Have you already completed the weekly at all? Completing the highest difficulty Weekly will get you 9 strange coins. granted I think it’s either level 30 or 32.
Have you maxed your marks out for the week? If not, run some strike playlists to max them out, and buy the cheapest Vanguard legendary armor. With maxed marks you should be able to purchase 2 legendary armors from the vanguard.
So wear your Willbreakers chest piece (Should have light 36 instead of 33 or 34, whatever the vanguard max is), so that fully leveled will be your best bet (Don’t trade in your Radiant shards, you’ll need those to level that chest piece - Maybe keep your Radiant energies to convert them to shards if needed).
With your Willbreakers chest piece and another piece of legendary gear from the vanguard, that should start to get you up there. You’re at least level 27 right now, so get some friends to drag you through VoG. You’ll get lower leveled legendary gear, but you’ll get ascendant mats, and at least the gear is designed to get you to level 30, so it’ll be better than any Rare (Blue) armor you’re wearing.
If you have the motes to support it, try your luck with an Exotic Helmet engram from Xur. This should get you high enough to do a reasonably high leveled Weekly which might net you some legendary armor, but will get you more strange coins.
Edit: Do you have HoW DLC? If so, do Petra Vanj bounties, but regardless of whether you’ve completed her bounties or not, explore the areas like Skywatch and Forgotten Shores in the Cosmodrome, or The Citadel in Venus, and there’s a few other areas. Hang around and you’ll see messages pop up saying “The Wolves are prowling”. These are mini events where after you kill the 4 or 5 waves of Wolves then you get an Etheric Key. You have 1.5min to find a yellow glowing chest hidden somewhere in that zone. There’s generally 4 or 5 spots that they’ll spawn so get up high and look.
The reason why I’m suggesting the Wolves bounties is because these chests have the potential to drop legendary items. Prior to the HoW of launch I was doing Petra’s bounties and in about 15 wolves runs I ended up finding 4 legendary engrams. Might be a better payout than the crucible.