I don't believe in something so absolute as, "Never approach!" That said, I think a heuristic like, "Don't go in swinging with a SH aerial when the opponent is trying to pretend that they're vulnerable to it but aren't really as a result of the immense space they've put between themselves and you to ensure that you can't chase a laser effectively," is probably reasonable. And then I gave a bunch of ways of identifying if they are doing just that.
Regarding approaching in a bit more of a general sense... I'm gonna level with you, I'm not really sure what constitutes approaching at this point in the game's development and I don't really care either. It's always seemed like a big, vague, poorly-defined umbrella term that has been modified within each region to some degree, which results in delicious lapses in clarity in these discussions. As a side note, it was also adopted by WC and therefore is now part of the Gamma Fraternity.
I feel that throwing SH aerials at an opponent pinned at the edge can be an effective choice certainly but like any other play it sports its flaws. I feel in general the high momentum approaching SH aerial vs a pinned opponent is misunderstood because I don't view it as really that strong. I actually do have a soft spot for forward SHs that pull back or cut momentum to control a tighter space, but whenever you take a big swing at the opponent to close distance and reach them from further with your jump, you're radically shifting the part of the stage you exert most presence over. This can work agaisnt you because moving the reach of your character so that it overlaps the foe's current position so much can run into snags if they spot you repositioning by attacking them and they roll through you. This sounds goofy, but it actually can happen (hell, I think it's amazing and needs to be used more) and is a reasonable outcome because SH aerial doesn't take much less time than roll at all and Falco's dash is slow. The good position you had to systematically remove their options has now been flipped on you. In general Fox is the better gimper of the two as well, and is very good at gimping Falco, which means he enjoys Falco being pinned almost as much as vice versa. Creating opportunities for reversals like that to happen are a good way to weaken the consistency in your game.
That said, I don't think it's so cut and dry either. I think Falco's approach in this instance shines where he uses lower momentum dash SH aerial setups to condition the foe to not roll inwards because by pulling back during the SH or simply using reduced momentum he's protecting the roll in option but also moving forward a reasonable chunk. Moreover, there's nothing that says you have to fade back before you catch the roll. You could approach and see the reversal being attempted and cut momentum then, which still enables a degree of approaching while tending to the fact that dynamic, long jump ins are generally most useful for stuffing opposing aerials and a variety of positional things such as hitting a retreating opponent (not an option vs people pinned at edge) or crossing up a shield. Part of the fun of Falco is getting the opponent at the edge so you can get rid of the need to do all that work to get a hit. That's all legit fighting and I try to avoid dealing in it whenever possible. If you want to play like that, I suggest you inquire with WC.
I think you can just hit confirm laser into a spaced f-tilt but I'm not sure what the timing window is like. I think we may have had a communication slip up somewhere too because I'm not really a fan of f-tilting into someone's shield if I can help it. I just know that tipped f-tilt combos from laser vs human opponents and conveniently tipped f-tilt isn't very easy (or sometimes even possible) to shield grab, making it a safer way to attempt to prod an opponent offstage. It's also much faster than the go-to options (bair) and can be done facing the foe. These lead to interesting little games in and of themselves.
edit:
I think your first combo should generally do more than 70% vs Fox if you want to be competitive in this game at this point in its development (the exceptions would be when you end with a smash attack trying to create a gimp / edgeguard or they have a really good SDI somewhere). That said, I think d-tilt and d-smash are excellent choices. D-tilt is nice at low percents because it leads to some interesting combos involving uairs and such that can create some good trajectory traps. And it's kind of cheating to ask if a combo move would be a good choice somewhere it is possibly viable in a hit sequence with me. Kind of like asking an alcoholic if they want scotch instead of grape juice at communion.
That said, I mentioned f-tilt specifically because I think it's overlooked a lot for heavier moves that seemingly give more of a bang for their buck. So I figured I'd talk about it because it's a move that rewards creativity IMO, has some unique traits to it (some mentioned earlier in this post), and the way it seems to feed and benefit from all the stress this character can impose upon his opponent (in really sick ways) creates unique openings and cool stuff is always more fun than d-tilt into aerial or shine WL aerial.
Anyway, let's start with KB. You say the low KB means that f-tilt doesn't accomplish much until it knocks down but I say the low knockback makes it good for gimping (both the setup and the finish) and the fact that you can tip it into most characters' shields as a way to see if you can poke them off the level without having to worry about an l-cancel can add a lot of consistency around the edge without compromising much threat. You can also probably get people offstage at trajectories they're not used to DJ sweetspotting at, opening up SH dair gimps or WD FF edgehog > react to recovery type situations. It also lightly pushes people out of that awkward space in front of and above Falco's head when you angle it up - a lot of characters take to impromptu desperation jumps and such because of their perception of Falco being vulnerable there. You can actually draw people into attacking that part of him just by facing them (remember to kick them though!) whereas if you'd turned your back to them in that same position you might have encountered a very passive, safe opponent and not gotten the free hit (and maybe a gimp or such?) since backwards Falco is stereotyped as the defensively strong one. People respect that guy.
This last bit is sort of a gimmick but also not. Sometimes when you don't knock an opponent over when they're waiting for an opportunity to counterattack, they jump the gun on committing to the counterattack because they tunnel vision on the fact that they can do it after being hit without realizing that they have been pushed out of range of their counterattack because they were at like 55% and hit by tipped f-tilt. This can be especially true when your character makes people feel like they're out of control of the pace of the game so much. The awesome part is that if they're pushed out of counterattack range, even without knocking them over there's nothing really stopping you from simply attacking them from there with a SH aerial, more f-tilt, etc. because it's easy as hell to make his aerials frame safe and if you poke or grab... well, those tend to be good vs disrupted, stationary foes anyway.
