You can alter the instances of System > Wait Time in the Event Sheet as well. To speed things up. I modified some of them while working on making changes this morning to what you had. I forgot to set them back to what they were originally. My bad XD. It has been a crazy welcome to the new week today.
Anyways, here's a couple YouTube Channels I highly recommend.
Xanderwood - He's a great resource, and I've learned a ton from a few of his tutorial series. This is a great place to start. His original Platformer series is fantastic, and covers many areas of Construct 3. Perfect place for beginners to start learning. And, all his videos are concise, and has good flow from video to video. I tried to follow along with certain devs on YouTube when I was just starting out. And, wound up getting super confused because certain Events, Variables, etc, would change between videos.
https://www.youtube.com/c/XanderwoodGameDev
FoozleCC - Fore more advanced topics, I highly recommend FoozleCC. Everything from using the latest 3D features of Construct, to complex mathematical formulas. He was slowing down with his YouTube Channel for a while(he had another child). But, the last time I chatted with him online, he was saying he's trying to get regular with the uploads again. I haven't looked over his uploads in a while. I developed the Player State Machine in my current major project, based off of one of his videos. Then, expanded on it, and added a bunch of things on top of it.
https://www.youtube.com/c/FoozleCC
Game Design with Reilly - I haven't gone through much of his videos. But, I came across his channel a few times over the past year. I just picked up using Construct 3 again about 10 months ago, but had a 5 month break from it over the Winter, while dealing with other things in life. The videos I have come across, have been solid though :)
https://www.youtube.com/channel/UC7wehUTim_FmesOi3l2qMQA
I'll be starting a tutorial series for my current platformer project as well. Showing folks how to build a fairly advanced Platformer game from the ground up. With all sorts of power-ups, falling platforms, etc. Not really anything educational there yet. But, you are welcome to visit whenever. Hope you all don't mind the plug XD. If you do visit, you'll notice I don't have any sound effects yet. I need to spend a day and find decent licensed sound for that part of it. Sound alone adds a lot to gameplay. Especially for one of the latest Player moves I've added, which is a Butt Slam like in Mario. Just added a few things that interact with that ability the end of last week, and today as well.
https://www.youtube.com/channel/UCVeduuNSqlZqQLbj09w2HAg
EDIT: I'll leave the question of all splatters be the same for each EnemySprite Destroyed, up to you ;). Unless Everade, or someone else wants to jump in. I've got a busy night/week ahead. Take Care, and best of luck!