with respect to simg stuff, I think the only one you ever need is simg2img. see https://gitlab.com/JBBgameich/halium-install/-/blob/master/functions/core.sh#L21
with respect to android tools, I assume what you need is adb and fastboot tools
PS: actually not everyone might needs simg2img. I think some android trees already create the image in ext fs format, then no conversion is needed. halium-install detects this, but in either case current halium-install will still check for the existance of simg2img upfront. Also, I think Samsung ports that install via heimdall don't use halium-install alltogether ... I don't know too much about Samsung ports. they may or may not need simg2img. Similar for fastboot. I think some vendors don't support fastboot but do smt else.
Bottom line, if there is a way to fix instructions to provide simg2img, adb and fastboot, that would fix it for everyone without sweating the details
