Welcome back. 
As this is not a question about book recommendations, I’ve moved it into it’s own topic.
LHP just means doing magick for personal reasons, working with angels is not what makes it RHP or LHP.
I think that’s not a good idea… I mean, why? What would you gain? They’re different beings and you stand a chance of just insulting both entities.
I wouldn’t play matchy matchy and confuse things unless I was very familiar with both currents and the entities felt and told me they were the same being. Work with each current as is until you understand it on it’s own merits. Or don’t bother with the pantheon at all and just work with the entities you are naming.
Lot’s of people here don’t work with so called “angels”. 
I don’t entirely believe there is such a thing… I work with any entity on it’s own merits, which means I do work with entities that others label this way, because I don’t believe there is a difference between them and the “fallen angels” and I just don’t care about some death cult’s opinions and politics. I meet them myself and make my own mind up based on the one on one interaction.
There’s no rule that says you have to use the Solomonic method, which is what you are referring to when you talk of calling angel names to conjure. Most grimoires and especially modern ones don’t use this. Pick an evocation method and summon whoever you like.
There’s a few tutorials on here, this is one of them: