More customisability in /placefeature

Snapshot 22w03a (the most recent at the time of writing) introduced the /placefeature command, and I LOVE it. However, I think it could be improved. From a quick test I found that there were at least dozens of variations of just 'minecraft:spruce', each with different heights and leaf arrangements. My suggestion is that there should be a way to spawn a specific variation of a feature. I don't know how these features are generated, so I'll include two possible ways to achieve my suggestion. Which one is relevant will depend on which is the correct case. I'll continue to use 'minecraft:spruce' as an example. 

1. If there is a pre-determined and limited set of features. In this case, '/placefeature minecraft:spruce[5]' will work just fine. 

2. If the feature is generated from random parameters. In this case, just allow us to set the parameters ourselves. For example (and I'm assuming what the names are) '/placefeature minecraft:spruce[height=8]'

Not setting any specifications makes the command generate a random feature, just like it does now.