1: the Iraqi military will likely not be a pushover like they were in 1991. In material terms, they are much weaker than they were 11 years, but in morale terms; there's a big difference between fighting for a territory you've just annexed and fighting for your home.
I disagree with your reasoning.
I don't think there is a "morale" issue the way you described it. The Iraqi soldiers include many 1991 veterans. They know that fighting the US = certain death, but surrendering to the US means staying alive. They can reasonably expect that they will not be killed wholesale by Americans once captured, since many were not last time. experienced soldiers will tell this to the younger ones.
Also, since US intent is to remove Hussein, troops will surrender more quickly, knowing that they will not be going back to face the same dictator after having failed ot fight for him.
2: Iraq will not deploy its forces so the US can easily smash them. There's already indications that they're going to go urban rather than let their outclassed forces be smashed into pieces in the desert- and the US forces will have to deal with at least the major pockets of urban fortifications. If not, you're leaving enemies behind in your rear; never smart. Casualties among both sides will be higher.
I think the Iraqi civilian population will be happy to clear out of the cities before the Americans arrive (through our psy-ops campaigns, we will give them notice), making this much easier.
3: Saddam will probably use his last remaining ballistic missiles on Israel. He used this tactic in 1991, with his survival at stake I see him doing it again. However, Israel has a ABM system (Arrow) in place; and improved Patriot PAC-3s (the Patriot used in 1991 was a dismal failure, despite lies to the contrary) from the US *may* render this tactic ineffective. Then again, it may not. Israel, in its fervour, may use it as an excuse to settle accounts with all its 'enemies'- especially the Palestinians in the Occupied Territories. This will inflame the Arab World, period.
Hussein may launch toward Israel. But I don't buy the "Arab world" response. Who?
Saudi? The rulers are more concerned with in-country problems, such as combatting fundamentalists. They can't unify against Israel. The rulers need every oil dollar they can get, because they are literally paying of regional religious leaders to keep the fundies in check and preclude civil war. One step against Israel and we can threaten to slow our oil purchases; in fact, this is porbably going on in secret negotiations now. Corruption and greed by the House of Saud has reversed the oil weapon: it has become (politically) a liabilty to them, not an asset.
Iran: they're not Arabs. They're Persians, who hate Arabs, and Shiite, who hates Sunnis. They won't align with Arab powers.
Egypt? Maybe, but Israel has already shown an ability to destroy them.
As an Army Ranger I trained with Egyptians. Officership in their Army is based on status not merit, anyway, suffice it to say they are a weak military force.
So who is left? I just don't buy the "Arab world" thing. It is a misconception.
4: The Kurds will go ape if they see their oppressors getting defeated. This leaves open the possibility of Turkey getting involved; if the Kurds decide to try and establish their dream of Kurdistan.
Turkey wants nothing more than to get into the EU. They will tread carefully around activities that wil cause them to be denied access.
Just my opinions.....