Not every move needs to be good. Zelda is a solid character without a good jab. She has at least 4 moves that can semi-fill that role anyway, depending on the situation (ftilt, dtilt, dsmash, neutral B).
I had a mild seizure from just the thought of using NeutralB as some sort of jab replacement

. If it hits it's okay, but because of it's strange hit boxes (Zelda sure seems to have a lot of these...) you can either
1. Hit them with all the hits and knock them back decently, but ONLY if you're in extremely close proximity to your opponent (ideal) or
2. It'll do like, 1-2% damage with no knock back or hit stun, and you'll be a sitting duck.
Not to mention it's incredibly punishable upon shielding. It looks fast, but it only really hits on like, Frame 13. AND, even if you do hit with it, sometimes people will still manage to get a hit in during the attack and essentially interrupt it anyway, stopping it completely. In no way would I ever consider Nayru's Love a semi-jab replacement. It's too unsafe and risky.
Even as a reflector, it's severely limited:
Startup: 1-12
Hitbox: 13, 16, 19, 22, 25, 28 (6 hits)
Cooldown: 29-59
IASA: frame 60
Invincibility: 5-11
Reflects: 5-44
The after lag is pretty bad. Even if you do reflect the projectile, what will most likely happen is you'll get hit by another of the same projectile anyway because of how slow it is with it's wind down.
But anyways, Nayru's Love is hardly a priority to fix. It's mediocre, but I don't mind it that much. If you really REALLY need to reflect something, it gets the job done (as long as you aren't baited unto using it). If only the invincibility and hit box frames overlapped a little...
Ftilt I can agree can be a good semi-jab replacement. However its cool down limits it's usage for any sort of jabbing and it's still pretty punishable upon blocking because of that. But honestly, I don't have any problem with Ftilt the way it is now. Sometimes though, I wonder if it'd be better if it's knock back trajectory would just be changed so that it would match something like Ike's Ftilt (not power-wise people). But that's just my curiosity wandering. I'd just want to see how that would work out.
Dsmash I think I explained in my previous post. But once again, I don't have any real problems with it. Trying to say it's a semi-jab replacement seems a bit silly though... no offense to you!
Dtilt. Ah yes, the only "real" jab" Zelda seems to have. Comes out on frame 5, with a 6 frame linger. Not to mention it's cool down is comparable to her actual Jab (literally, this has 1 extra frame of cool down compared to her Jab). But the problem with this is it's coverage. You need to be pretty close for this to hit, and it only covers the ground whereas most jabs can at least hit people that are slightly mid-air. Though once again, I really don't have any problem with this move the way it is now. This is probably the closest Zelda has to any real jab however.
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Her Jab is so close to being usable. Like, some small adjustments would make it really that much better. I really don't think improving her Jab is really going to overpower her.
Honestly, if they fixed Zelda's Jab like Ryoko suggested earlier, I'm pretty sure that would be it for Zelda's improvements.
...Unless they make Dair sweet spot even when opponents are on the ground! Mm... Ganondorf-esque Dair kills... (totally not expecting Dair to be changed like that

No matter how amazing that would be).
Lord. Sometimes it's just exhausting to explain Zelda so much, since she's not really well known. So many misconceptions about her...