okay scabe I have to disagree with you a little when it comes to whiplashing.
Im a pretty consistent whiplasher and I must say that as long as the trajectory of the move allows you to whiplash you just have to react, and if you can react with correct DI then you can add some input too, like a Airdodge and a press on the attack button. Whiplashing is best served as an antidote against low trajectory moves which otherwise would wreck link as a character. otherwise, the link main in todays metagame DIs up to get a lot of height and with that a lot of time to pull and shoot/ throw projectiles and /or attack the gimper with fair or coming down from above to sheild his recovery witha dair or FF airdodge through and zedge.
link can also avoid the hardhitting hitbox of say your nair and exploit the weaker to get above you by starting to airdodge and then right after your nair have commen out zair to cancel the Airdodge and get hit. This is a bit situational though and requires good timing. He can also use this to airdodge through one of your attacks and then tether the stage, canceling the ending lag from the airdodge. Then we have a bag of super situational tricks in tha bag too XD. total momentum stop, dair bouncing, bombjump, wallbombing, I probably missed hlaf of that stuff. its not really implemented in the general link mains game yet though(some link mains have a few speialities).
Anyways, if link gets below stage height in his recovery he should be doomed and if you get him offstage one hit with anything that hits him away kills him. You might have noticed that links recovery sucks lengthwise(it has lots of tricks and mindgames though, as mentioned above). You will probably be able to gimp him, and its gimping link you should go for,
Link onstage arent bad, hurting projectiles, large hitboxes, 8 or more(depending on how you count) good kill moves, projectile locking combos(bombstool, BAL and ReturnRangBlast(pretty new not that much used actually, anyways the link main throws a bomb at you when you ride the rang and this puts you in tumbling state from the bombblast but instead of being sent into to the air it drags you towards link, guess if you will eat another hit, guess if it is charged XD)). You will probably eat a lot of projectiles, its half links metagame after all(the other half is DI well), so count with that.
When you are close to link combing him will probably be easy for you, but mind that if you are at higher percentages out of nowhere a dair can come out to catch you as you are juggling link, the link main wants to keep you off and keep you under control in some way I think, since combing luigi isnt that easy, we can hit at your sheild as much as we want if I understood everything correct so if its not already a part of your general metagame, dodging or just spacing correctly(lol of course spacing is a part of your metagame XD) will be a very important way to avoid getting hit, links fsmash, dtilt, dsmash, ftilt, fair second hit and dair all give good sheild knockback so you will just slide.
Luigi kills good, killing us will probably not be that much of a problem, compared to many other characters.
and then we has gotzors our beloved zair, it combos, it spaces, got great range, set knockback and damage(two hits, 4%+6%), links third fastest move when it comes to startup, autocanceling. It allows us to hold a bomb in hand, we can add invincibility frames to it by airdodging first(most link mains zair by pressing sheild + attack to always get the option to get these invincibility frames if needed, since the zair can cancel the airdodge anytime instantly). oh but you are short, so its not that effective against you. XD, still its really useful, it can kill an aerial aproach or be links aproach move against you, or link can use the hitbox to just hold you off as he retreats. to get around the zair power sheilding is the best option, but hopefully the link will use diffrent timings. Anyways, its not imba, its links most broken move, but not a mach tornado(for sure lol).
I dunno anything about how you might use your luigicopter(or what that down b move is called).
anyways its probably tilted a little in luigis favor, luigi got good offstage game, is short(**** you), is good at damage racking and can kill easily. Though luigi have a bit of a range problem and light alo he dont have something to move link to the edge and set up the gimp, so he have to work for it more than say D3 or gaw(dsmash sucks, you never know how you should DI it). say somewhere around 60:40 55:45 luigi probs.