I'll share tips/tricks that I feel I've either discovered or experimented with on my own.. so i won't share any other samus's tricks without their discretion
Bombs:
Out of bomb crouch canceling (Raigoth cancel/bcc), Samus can buffer a variety of commands
The most useful one is probably dtilt because it comes out unexpectedly fast and being in morph ball form gives her a smaller profile, a delayed projectile to worry about, and good spacing options.
To buffer the dtilt, hold down to bcc and just tap A.. pretty simple, but how the game recognizes inputs it optimizes the bcc "down" command and the "A" command to buffer the dtilt.
Instead of dtilt, you can buffer down-angled fsmashes, instant dash attacks, etc.. that's basic bcc stuff.
For more defensive options, like with MC buffers, you can buffer shield, instant spot dodge and instant roll (if performed correctly, no landing + shield startup frames are visible). To do the instant shield, just hold down near the end frames of the bomb laying animation and hold shield. To buffer the spot dodge, hold shield and tap down twice. The first one initiates the bcc, the second one buffers the spot dodge. This is pretty useful if the opponent expects a dtilt and spaces accordingly.. The last one, instant roll, is a bit more difficult. You need to hold shield, tap down, then make a quarter circle forward/back motion (QCF/QCB) similar to arcade fighter input. By rotating the stick a quarter circle, you buffer in the down for the bcc and the forward/back for the roll in a smooth motion. I don't think its necessary to perform the quarter circle if you can press down and left/right really fast, but it helps.
Against a shielding opponent, bombing past them into a bcc fsmash eats their shield, pushes them into the bomb, which eats their shield a little more. Sometimes, opponents tend to drop the shield after the initial fsmash/dtilt and forget about the bomb, which helps to setup another fsmash/dtilt. YMMV, but I think it's decent shield pressure.
Samus can cancel her ledge jump animation with a bomb at the very instant she leaves the ledge. This makes her return to the stage very very low to the ground, with a delayed projectile, and the ability to bcc into anything, really. She can vary the height at which her jump is canceled by timing the down b, and she can DI back to the ledge, off the ledge or into the stage. I think this is better than simply ledgedrop dj down b because ledgejumping counts as a "ledge animation" and I believe you're granted a few invinicibility frames for it.
That's probably all for now.. I just wanted to "publish" my bomb stuff.