I am quite excited to see what you have discovered, xyro. I remember spending literally months in melee trying to perfect super bomb dashing and all the charged shot and down smash tricks that came with it.
As for normal bomb play, heres a list of situations that I believe they are useful in:
1. When recovering from the upper right/upper left corners of the stage, to stall the opponent out of his jumps if he chases after you. This requires good knowledge of how far out the character can safely chase you, but when the opponent must go back to the ledge then this is usually a good time to recover safely.
2. When your opponent is spaced about the length of Samus's roll dodge, a retreating bomb can be dropped to create a ground 'wall,' forcing your opponent to charge in before the bomb explodes or go to the air. Again the opponent's character matters (obviously NOT good with MK and his stage sweeping tornado or something), but this is usually a good option if you want some time to charge/spam, or if you want to try to force your opponent to attack from the air.
3. When your opponent is on the ledge and you do not feel safe going on the offensive, a dropped bomb that lands either right off or right on the edge can cause players trouble because they have the added worry. Also, by doing this you are put above and to the left/right of the opponent, which allows for quick zairs for arial recovering opponents, uairs for roll recovering opponents, and a bomb to the face/ any follow up for a get-up recovery.
4. this is VERY situational, but dropping a bomb when near an opponent and bomb hopping to the other side can lead to nice jab>bomb> anything you want. I would not recommend this, but safely getting into a situation where their is a bomb on the opposite side of your opponent, and you are on the other side, often forces the opponent to retreat/ allows you to punish.
5. In the air I sometimes use a bomb to simply 'hop' over a threatening attack from a grounded opponent coming up at you.
These are the main ones i could think of right now, but I know their are many other ways to use them as well. Generally bombs just allow for some creative situations, and they are by no means useless in my opinion, unless they are spammed.