Thank you for your feedback.
I used javascript and Phaser to build the game. At first I wanted to target mobile devices using Cordova, but then I though maybe I should learn C# and unity so I could target more platforms without worrying about the build tools. There are a some missing features such as boss fights each 10 waves, more power ups and weapons and player stats (kill ratio, accuracy etc) along with a leaderboard on each stat.
The core gameplay is exactly the same as the game in the video you posted. Maybe you could add the features that I skipped in Front Invaders.
Here the source code of the game if you are interested to check how the game was build.
Thanks again for the feedback and good luck polishing your game.
Don't forget to post the link of your game when it is ready !