You're in luck with Update v1.34 as secrets have been added to the game, happy hunting.
The frame drop from firing the Love Gun hopefully have been fixed in the newest update although tinkering with the games graphic settings can also help just in case of extended performance issues.
Imp models are currently being re-worked and I'm hoping to get them finished by the end of the Jam version of the game, if not then they will be updated in the post-jam release.
I'm looking forward to seeing what you do with your own FPS in the future my friend, If you wish to try out the engine I'm currently using it can be found here: Easy FPS Editor CE v1.10.5 by Clark
I always look forward to feedback and I thank you for your continued support. :)