I disagree a lot with your first statement. Stats mean a lot for herons. Or more specifically, their magic (and resistance) mean a lot. They heal adjacent units equal to their magic level. That may not seem like a lot, but if you BXP a heron a bit (personally, I used Leanne), you can get their magic level to 30 (transformed) - that's the cap though, but they're likely to cap it. So essentially, Herons heal their magic level to all adjacent units.

And, personally, I feel there's no harm in having a heron with me on offense. They survive most mage attacks rather easily, and preventing the enemy from coming in melee range really isn't that hard. Additionally, they can keep a unit like Ranulf or Skrimir transformed 24/7 (with Valor), using just 1/5 of the heron's turns.

Edit: Oh, and about the Laguz gems. You'll use Kurth over Giffca, I'll accept that. But Ena or Gareth? Not a chance. Ena is completely terrible, other than her aura, and Gareth has far too low resistance. And Kurth won't need one in the 5th chapter (obviously). You could also argue that dragons do not need a Laguz Gem at all. After all, a Laguz stone is bound to keep them charged for 15 rounds (with attacking each and every round).

As for a story related nidbit - I always assumed that the herons would go extinct after Leanne, Rafiel and Reyson. Apparently, that's not the case. In my last reason I did, for some reason, have Leanne and Naesala get an A support. The ending thus said that they got married and had two children; a heron girl and a raven boy.

Supports still affect endings?

Dagnabbit, this game is going to make me insane.

Also Nephenee is basically the Angel of Death now.

They do, but to a far smaller extent.

For instance (this is a bit spoilish, but not really).

One person leaves Tellius for good, going to Hatary (or well, across the desert or something).

Now, there are 2 characters who can go with him; assuming they have an A-support with him.

(This is the ending, not a chapter).

There's another where

One makes a packing company

The other one either becomes a duchess (or something) of a region (no support) or marries the first person and joins the package company (A support).

Then there's a fair bit of conversations you can only hear if they have an A-support.  (In the "INFO" section).

If you have this attidute when you enter the final chapters, you'll wish your Heron had a little higher stats no matter where they are placed.

I attempted a playthrough on part 3-7 and realised how difficult it is to attack the black knight with Ike.  I didn't really do a lot of thought with passing over items with Ilyana, but without a speedwing it is almost impossible to attack the black knight in that level (getting to him is easy, hell I could practically steam roll the entire level with 4 characters)

It's piece of cake. All you need 27 speed on Ike, or you can't do it. Just let the Black Knight attack Ike indirectly (or directly if you have Nihil on Ike). If you don't have 27 speed on Ike, and no speedwings, simply use BXP on Ike, and reset if he doesn't speed up. I know that's dull, but it's better than to not get to talk to the BK.

I played it on hard just a few weeks ago, and thought that 3-7 would be impossible (had never tried talking to the Black Knight before), but surprisingly - it was piece of cake. The main problem (for me) was the Daein army, as my Jill had the most exp, and I had "stolen" her with Haar.

I just started a new play though of Path of Radiance so I could pass the stats on to Radiant Dawn.

I'm planning on maxing out

Ike, Sorren, Oscar, Boyd, Rolf, Mia, Ilyana, Myst, Marcia, Brom, Nephenee, Sothe, Jill, and Haar.

I don't get why anyone would pass on the stats. All you really do is make the game easier, isn't it?

I made the mistake of not paying attention to his speed (and I had no speedwing).  So I only had a speed of 25 after using BXP and nearly soloing the level with Ike.  Taking a look at Serenesforest it looks like Ike without any speedwings will almost never reach the 27 speed prior to promotion.

On this playthrough, I have now given up on trying to attack the black knight, unless I get I can manage to get that 27 speed on the next attempt (very unlikely as I'm 2 short and chances of BXP and level up giving me speed is unlikely)

As much as I love the challenge, I also like having super strong units

Also, I think there is like 1 scene in Radiant Dawn that you can't get to unless you pass on stats. Of course, you could beat Path of Radiance without maxing people out and still do this.

you might want to see Ilyana on every stage because she is nice looking but it is a mistake, just don't do that!!! trade her with zihark (yeah 2 swordmasters ) or use a fire mage (tormod or callil [she is more useful on Radiant Dawn than him though )]) if you want a different anima user from soren. I use Rhys cause i'm a little addicted to Priests/Bishops but he is not that good.