Hacking Some beginner questions + Flashcart recommendations

[Aglaophotis]

Got AL9H + Luma!
Thank you for all the help.
I must say it was pretty straightforward and absolutely not difficult to do if you take your time and follow the guide closely. Those unpredicted black screens are scary though... For a moment I thought "Ok, that was it... at least I was a proud owner of a 3DS for a few hours", haha.

I got a couple questions.

1. I want to clean up my SD card and delete everything unnecessary. The guide says this should be on the card:

+ 3ds
+ files9
+ hblauncherloader
+ luma
+ Nintendo 3DS
+ arm9loaderhax.bin
+ boot.3dsx

But it also says

You can remove your NAND backups from /files9/ as long as you still have them backed up to a safe location.

What are the files I can remove from the folder? Th NANDmin.bin is my NAND backup, right? Is there anything else I can remove?
This is how my files9 folder looks like:

Spoiler

And this is the backed up one on my laptop:
(I also have another folder with the otp.bin)

Spoiler

2. In case I format my SD card, what steps would I need to go through to have everything set up again?
From Section V - Injecting FBI?

3. Is it safe to use the "Format System Memory" option in the system settings? Does it only reset all settings/installed games/saves, but won't remove anything AL9H/CFW related?

4. Can I safely fiddle around with everything, install/delete apps, play around with some settings, etc. without the risk of messing something up or even bricking? Is there anything I should avoid?

 

[Xiphiidae]

~snip~

1. There's not much point keeping your NANDmin.bin & NANDmin.bin.sha on your SD card, but ensure that you have them backed up, preferably multiple times. You can also delete all of the FBI files in files9, but I recommend keeping the one for your region and console type, as it doesn't take up much space and you don't know when you might need it.

It would be a good idea to copy over your files9 folder to your computer again.

2. Yes. If you format your SD you'll have to go from 'Injecting FBI' again, as you will have to to do that to be able to install .cia files.

3. I haven't done this myself, but I am virtually certain that it is completely safe. It will not remove A9LH, but it may wipe your SD if you have it inserted.

4. Pretty much, yes, as long as you have your original NAND backup (or preferably a more recent one, and a recent SD backup if you care about your save files/installed games etc.). Just make sure you don't do anything that messes around with FIRM (for example, downgrading NFIRM with dsiwarehax; this will brick if you have A9LH installed). It's always a good idea to wait a little bit before updating when a new system update is released. Finally, don't delete anything on your NAND with FBI/GodMode9/etc. unless you know exactly what you're doing. Make NAND backups every now and then, and don't mess around with system stuff.

 

[Aglaophotis]

Make NAND backups every now and then, and don't mess around with system stuff.

What would be the benefit in more recent NAND backups?
Does this mean new backups will already contain A9LH? Because if that's the case I might also keep my original backup, just in case so I could restore the 3DS to it's clean state without any hacks. (if I want to sell it some day or something like that...)
Or is there always a way to restore a clean NAND without A9LH?

 

[Xiphiidae]

What would be the benefit in more recent NAND backups?
Does this mean new backups will already contain A9LH? Because if that's the case I might also keep my original backup, just in case so I could restore the 3DS to it's clean state without any hacks. (if I want to sell it some day or something like that...)
Or is there always a way to restore a clean NAND without A9LH?

You should always keep your original backup, and make several copies of it. Restoring this backup is the best way to remove A9LH if you ever want to. There are other ways to remove A9LH, though I do not know much about them.

The benefit of making more recent NAND backups is that if anything goes wrong, then you can restore a recent backup and hopefully not lose much. It's good to make SD card backups for this same reason.

 

[Aglaophotis]

Thanks for the clarification.
I assume the "Dump NAND" option in FBI is the same as doing it in Hourglass9? Or should I stick to Hourglass for NAND backups because it boots before the system?