This is a quick poll.
How many applets would you like to have in Diablo5 theme?
The best number for me is 9.

I find the current number works fine.

If the theme allows for more but works the same if fewer are enabled, that doesn't bother me at all.

If allowing for more reduces the title bar, I'd prefer not, but I won't be too upset.

I'd also want it to continue to work as well as possible in landscape mode.

Overall, I'm just really pleased that Diablo5, Telescope, and Opera have breathed new life into my N810

Can it be 9 in landscape and 7 in portrait?

No. Same thing for both modes.
The reason why I really wanna have 9 applets is:
1. Telescope applet
2. Advanced power applet
3. advanced brightness applet
4. load applet
5. IM applet
6. connection status applet
7. big statusbarclock hours
8. big statusbarclock minutes
9. Telescope Launcher applet (without it 8 is ok) or minigpsd applet.

I would say about 10. My list looks a lot like Kroll's. But I wouldn't mind having some space for a few extra ones. I'm stil hoping for amazing new upcoming apps

What is the max amount in portrait?

inoshishi, remember, more applets you have - less space for Title. Especially in portrait (9 will kill Title "slightly less than fully", 10 kills Title completely). It means you will unable to reach menu by tape on application title (because there is no Title at all in this case) and you can't see Title.
Ok, lets take out 2 telescope applets (we already have home (F5) button to launch Telescope or Launcher) and we have 2 additional places. Think about it carefully.

Currently I need 1 applet space for the notifications thing (the notifications and applet-switcher normally in the bottom left for the default themes). If that could be worked into the application switcher in diablo5 (the upper left corner), that frees up some space.

Typically I have:
1. Advanced Power
2. Advanced Backlight
3. Connection status
4. Load applet
5. IM status
6. Notifications
7+ GPS, USB, etc (as needed)

I don't have a title in portrait with 7 status bar apps and tapping the close button (X) opens the app menu instead of closing window.

If you have a small number of status bar apps, say 3, and the theme supports 9-10, would most of those apps be buried in the close button? Or can the theme be made to align them to the left side?

auouymous, nice question.

Yes, hildon can align applets ONLY to the right side and this is a really pain in my ***. Mitrandir currently is trying to change it and make applets align to the left side so it will be not so bad, BUT

Title position is static. If we decrease quantity of applets from 7 to 3 we will have 160 pixels of free space between applets and Title. According to last Diablo5 version things are pretty the same, but here we will have space between left edge of the screen and applets.

So IMO I should make a few builds of the theme with different numbers of applets allowed. Anyway I want to wait a few days and see what Mitrandir can do with Hildon, maybe we will find better way.