Which is easier to play between the Shadowrun or Star Wars current editions?

[kid america]

I'm looking to run a once a month sci fi or cyberpunk game session that is not a campaign, but is more 1-2 game sessions adventures/missions. Something that allows players to make new characters whenever they feel like and build them quickly.
Something plays and feels more like a good comic book adventure or sci fi short story.
A game system lots of players know and want to play.

I want the RPG to be something that is easy to learn, easy to run, easy to build characters and doesn't have the enormous d20 character build option massive campaign world feel.

I've tried putting together a Savage World's sci fi or cyberpunk game like this but I could only find 2 players in my area despite advertising for months on multiple forums.

So this thinking brought me to Shadowrun and Star Wars.
I know players love both games and it should be easier to find and recruit players.
I know there are beginners box sets for both as well as full core rulebooks.

I'm looking to hear from GMs and players who have played both as far as:
• Ease of learning the rules
• Ease of teaching the rules to new players
• Ease and quickness of character builds
• Ease of putting together a game session

I'm hoping to be able to GM something that is quick fun and spontaneous so no matter what level of RPG experience you have you can show up at a game session, play and have fun.

I don't want to build my own world or design long drawn out adventures.
I want a prebuilt setting and short adventures I can customize quickly and on the fly.

Thanks

kid America