As the man who Rey is most likely referring to here, I'd like to put my two cents in as a Little Mac main.
For Glory Macs are a very different breed of cat then people who actually have some semblance of idea what they're doing. F Tilt is a monster of a move. Safe when spaced right, does good damage, comes out fast, AND has kill power. That's not a fun combo. Just make sure you space it right, otherwise it's REALLY unsafe.
Forward Smash is an interesting beast, given it has three variations. Unangled is vanilla launching power, straight forward, not much to talk about. Angled up doesn't do as much damage, but the launching power and how much space it covers is actually ridiculous. Any amount of rage + decent % on the opponent means a good read and they're probably dead to that. Angled down is another interesting tool Mac has. Whilst it launches you pretty much nowhere, it does HUGE amounts of damage as well as pretty much murdering your shield. Angled down F smash can break shields REALLY easily if you aren't careful. Also, if your opponent misses their tech, you can ground lock them with a short up Dair. Fun!
"But how does he kill if you can't land those?!" you may cry, but Mac has one easy setup into a kill that isn't KO Punch or the previous moves. That setup is Down Tilt, one of Mac's best tools. Fast, pretty safe, good at 2 framing people's recoveries(Rey can tell you about that one), combos into full hop Forward Air for the infamous Air Mac stuff, and most IMPORTANTLY it is usually is a true combo into Up B. Mac's Rising Uppercut from the ground has ridiculous launching power, and will kill you at roughly 105 I believe. I need to do my testing again I lost my notes a while ago.
A few notes on Mac's aerials: They suck yes, but they DO have their uses. Down Air is an untechable meteor that can kill unsuspecting people really quickly. Forward Air is a great combo extender from down tilt, but you have to full hop and then fast fall it to make it work. It's decent for gimping as well, particularly characters like Robin, Captain Falcon, and Ganondorf. I haven't found much use for Back Air, but Up Air can be useful as a combo ender from Down Tilt for a little bit of extra percent. As for Nair, it's just a...very very weird move. You can do some stupid things with it. Nair > Footstool > Nair > Footstool > Nair > Footstool > Rising Uppercut is a real thing. Good luck pulling it off, I sure as hell can't.
Some final things to get you started on Little Mac: Patience is key, as Rey said. An impatient Little Mac is a dead Little Mac. With that said, don't be afraid to force the issue! You have a wealth of safe approach options at your disposal, including but not limited to; Forward Tilt, Down Tilt, single Jab, and for those with the execution, perfect pivot Up Tilt. Up Tilt is Mac's sleeper move, FYI. It's fast, covers a HUGE range(especially if you face away), and combos into itself. A good anti air for sure.
Finally, a couple easy combos to get you started as well: Down Tilt > Jolt Haymaker(Side B) does good damage and can get you away from the corner. Just make sure you don't do it too close to the ledge. Down Tilt > Forward Tilt is always solid, gives you good damage whilst not having the risk that your opponent might land on their feet and punish you for D Tilt > Side B. That combo is a little weird and doesn't always work the way I want it to. More testing is required.