So. I just did some rereading of The Lost Metal, and I came across an interesting quote from Marsh. When meeting the group while they're being held in captivity by Entrone. Marsh says that the Set can't compound using Hemalurgy because "Identity contamination prevents it." This implies that Hemalurgic spikes contain a bit of the Identity from the person they stabbed, preventing compounding.
If only there were some way to get rid of someone's identity... *Malwish airship crashes through window*
Yep, that's right. If you want to Compound with Hemalurgy, all you'll need to do is get a ferring or a misting to store their identity in an unkeyed metalmind and spike them. Spike yourself, and now you've got a spike without identity contamination. Do this for the corresponding metal, and you'll have access to compounding. Nice.
So let's say you want to use this to become the second Lord Ruler (as one does). I'd recommend you start by spiking a Duralumin ferring. This allows you to store Connection, and by tapping connection, you become more able to form relationships with others, or, you know, persuade them to ignore the spike in your hand. Then go for a Duralimin misting to Compound Connection, and now you can convince anyone to do anything you want. Use this to spike one of every other type of ferring and misting while having them store Identity, and you can acquire the powers of the Lord Ruler.
Thank you for coming to my TED talk.