My update on freezing:

Took out AM two weeks ago, cause the random freezes every couple sim days had become unbearable. Hadn't had a single freeze ever since.

Today I decided to give it another try.
Completely reinstalled TS3 (razor) and the framework. Patched it up to 1.4.6 in one go without errors.
Put in latest AM and Indie, no other mods.
Started a new neighborhood, destroyallhumaned it and threw one of the EA fuglies into it.
Freeze after 14 sim minutes, no way out other than killing it from task manager.

*Sigh*

PC is an Intel Quad, XP, 3 Gigs usable RAM, Nvidia GTX 275. Definitely no overheating or any other hardware related issues.

Actually it's about two minutes realtime, saving your sim many, many hours wasted for tending several generations of slow growing plants. Maybe it sounds more complicated than it is.

My sample size is pretty big, and I've never seen a less than perfect death flower either. So I guess they're always perfect.

There's a simple way to find out both type and quality of uncommon and rare seeds by exploiting a flaw in the "choose bait"-dialog for fishing. If a sim has both fruit and seed of the same plant in his inventory, only the seed will appear as a bait.

So if your sim has a heap of uncommon seeds in his inventory, and you want to plant only the best one of each of the four possible types of fruit, do the following:

Dig a tiny water hole somewhere on your lot.
Make sure your sim has (at least) one piece of each uncommon fruit in his inventory.
Grab the entire stack of uncommon seeds (the trinagle corner) and lay them out on the ground in a line from left to right. Now you have the most valuable seeds (by §§) on the left end.
Put the leftmost seed in inventory. Hover over the water hole to bring up the "choose bait" dialog. Scroll to the seed to read it's quality. Now check which of the four uncommon fruit is not offered as a bait. That's the type of your seed. Take that seed out of inventory and put it somewhere else for later planting.
Put the next seed from the left of your line in inventory and repeat. If it's the same type of plant, sell it, otherwise put it away for planting.
Repeat until you've found one seed of each plant.
Now you can sell all other seeds, as they are lower quality than  the four you sorted out.

The same method works for rare seeds too.

As this thread has shifted from the 1 am lag to freezes, I can contribute something:

I hadn't plaved TS3 for about a month. After updating AM a few days ago, I found out that my custom, destroyallhuman'ed neighborhood that I had always used to start new games didn't work anymore, it would freeze within seconds. Later I realized that destroyallhumans or destroyallnpcs always leads to an infinite freeze now. Eventually "exterminate 100" gave me a working neighborhood without too many fuglies. I guess there's a problem with creating some particular NPC causing this. It doesn't matter which story mode driver I use btw, I tried Indie, AM's and EA's.

I still have freezes once in a while now. In most cases, I can just terminate the process and restart. Once I had to take out AM and run a sim day without it though in order to get the game working again. (I have a save right before that reproducable freeze if it's of any interest.)

Another reproducable freeze I had whenever I switched to "suck up to boss" at the restaurant career. There was no boss on my Sim's relationship tab, maybe that's why.

Which would explain why animations look so much worse than in TS2. Seems likely to me.