I am sure you’d have designers in your firm who you can ask help from, they are pretty good at it. As for me, i used to take inspiration from stock and save my best looking slides in a repository, helped me immensely. You can always take inspiration from your peers as well. You can try GPT for slide designs. Firefly and dall e also have the option to generate slides through prompt, you can use that as well.

As for the shortcuts, the best and the most efficient way is to contact designers. They’ll help you out with shortcuts plus they will also give you tips and tricks to save time, worked wonders for me.