If you are advertising it as an after effects alternative (which it looks like you are) then you should be trying to include all features that after effects has.
If most people use 20% of the features of an app, and you create an app that covers these most popular feature really well I think it's fair to call it an alternative. It doesn't say "full clone" or "feature parity".
I could not seriously pretend of a 'feature parity', if I can match 10% of features, that should good enough for most users. I'm not expecting the next Marvel movie to get its SFXs done with PIkimov.