So, I gather from the posts about 16:9 videos, that pI3 changes rectangular pixels to square ones when outputting. Which would explain why my widescreen captures turn into 4:3 videos. I work with Pinnacle Studio 12 for editing. I happened to right click on a thumbnail when choosing a video to edit, and found out that there is an option to choose between aspect ratios of 4:3 or 16:9. If I highlight a thumbnail that is a 4:3 and choose to change it to 16:9 it opens as a widescreen video. Yay! So there is a work around that I wasn't aware of. There may be some loss of quality, I don't know, or can't tell.
So my wish list for pI4 would be that it doesn't change the aspect ratios of videos containing particle effects.
I also think that shape-able blockers, say, with curved or bezier points would be handy so you wouldn't have to make so many points to block a complex shape like a human.
Otherwise, I'm having a blast with pI3. Thanks very much.