you could make a game with the fps tutorial assets and still have it as your own game.
for example i have a game called Time travel that sells for one dollar that has the tutorial assets. however there is multiple themed levels. and it is not the default "scene" therefore it counts as my own game.
from what i tell by the screenshots that you used the polygon scfi pack which costs 120 US dollars however even with a game budget that high the game doesnt look good. i once made a game with a 110$ budget and it is pretty well.
heres a tip for making a good game: add more levels and storyline.