Man I wish 1.996ghz was fine for every Erista because quite simply its not.
I've come across plenty of units that can barely scrape past 1.868ghz without overvolting, some very unlucky people can't push past 1.728ghz.
HERE WE GO
Nintendo:
GameBoy Color
GBA SP
GB Micro
DS Phat
DS Lite
DSi
O3DS
O3DS XL
Game&Watch Mario 35th anniversary
Game&Watch Zelda 35th anniversary
N64
GameCube
Wii 2x
Wii U
Switch Lite
Sony:
PS1 Slim 2x
PS2 Phat
PS2 Slim
PS3 Super Slim
PS4 Slim
PSP 1000
PSP GO
PSVita 2000
Microsoft...
I used them genuinely to archive files I had lying around even when my laptop had a perfectly fine dvd burner. I did use them to install things, but I will admit to using one to make an infrared filter for an old digital camera I had
If you're worried about memory, might I suggest taking an approach similar to Line-3DS. The app used to contain a .cia that allowed for 80MB of memory on the O3DS and 178MB on the N3DS. I doubt something like this could be done from a .3dsx file, but i'd love to be proven wrong.
They're in the nand somewhere, exactly where I don't remember. I did try running the settings app or dsi shop once and from what I remember they ran basically identically to their standard counterparts outside of some issues here or there.