I'm only just starting to feel my way around War Machine, so take what I say with a grain of salt 
Firstly, I was under the impression that your warcaster added a number of points to your list to use on Warjacks. Striker should be adding in 6 points, so you can take 26 points in a "20 point" game. So you might have a few extra points to play around with
For your lists, your first list has two very good models in it, but I think that having only two models in a 20 point game will mean you'll be hugely outnumbered. I have a feeling that the Thunderhead might be best saved for at least 25 point games, so you can get a few more models on the table.
You're third list is interesting, though I think if you got the Officer for the stormblades, and perhaps a few of those weapon attachments they can get (storm gunners), they might become a very potent force. If I was right about you having a few extra points to spend, perhaps take one unit of upgraded storm blades, and swap out the other unit for another jack?
Anyway, like I said, very new to the game, but hopefully that might help somehow
Firstly, I was under the impression that your warcaster added a number of points to your list to use on Warjacks. Striker should be adding in 6 points, so you can take 26 points in a "20 point" game. So you might have a few extra points to play around with
For your lists, your first list has two very good models in it, but I think that having only two models in a 20 point game will mean you'll be hugely outnumbered. I have a feeling that the Thunderhead might be best saved for at least 25 point games, so you can get a few more models on the table.
You're third list is interesting, though I think if you got the Officer for the stormblades, and perhaps a few of those weapon attachments they can get (storm gunners), they might become a very potent force. If I was right about you having a few extra points to spend, perhaps take one unit of upgraded storm blades, and swap out the other unit for another jack?
Anyway, like I said, very new to the game, but hopefully that might help somehow