Hello there! I love seeing other 
Canadiens on here! Manitoba represent!
While I agree there needs to be more to the checklist, I found going through the actual POH helps a ton - it is a sim after all (you mentioned the G1000, im guessing you’re piloting maybe a C172 Skyhawk, 
POH is here).
Otherwise videos on youtube on G1000 will help too (on flight plans and general usage (this one is on FSX - but the nature of sims is that they mimic reality so a tutorial on one sim should apply to another)), so will looking for your specific plane (WEH videos’ C172 Steam Gauge, there’s a whole lot more out there - Rob Machado’s lessons).
I found there’s ton of content that are specific to MSFS which is just perfect because its geared towards this sim.
In the mean time, you could go through the #self-service:wishlist and make a suggestion on there or upvote a similar topic such as this: 
Expand checklists to include after engine start and cover the whole flight
I hope these help and get you off the ground and safely back!