I usually end up playing Halo games on Heroic and later on doing a Legendary playthrough. With Reach, I kinda wanted to cut it short and go for the Legendary playthrough right away. I finished the first two missions and found it to be a horribly paced and unbalanced mess. Honestly though, it always was a horribly paced and unbalanced mess eversince Halo : Combat Evolved. It's a great challenge and to beat it is quite the achievement (or rather grind), but a worse game experience overall.
 
So I revisited my initial decision to go for the challenge first and decided upon playing it on Normal difficulty. Suddenly - all my complaints were gone. It isn't a pain anymore. No more being a frail everyman tiptoeing about like a scardy cat. On normal mode, I'm a daredevil. A slayer of legions. The demon haunting the covy world. It's a cinematic experience with a great flow and ebb of in your face CQB action and master marksmanship and vehicular action sequences. Doing what looks good and feels right. Getting into the act of being an uberelite Spartan. Thanks to the spot-on pacing I can achieve total immersion in the imminent fall of Reach. The game moves fucking forward.
 
Loving it. All of it. The campaign is fucking great. Playing the campaign on Heroic or even Legendary is, while being a great (and often unfair) challenge, detrimental to the overall gameplay experience. I recommend to anyone to disregard their skill level for their first playthrough and go for the cinematic experience that is the Halo : Reach campaign on Normal difficulty. It makes a world of difference. Truely - Normal difficulty is the way Halo : Reach is meant to be played for the first time.
 
All love for the Halo : Reach campaign played on Normal difficulty. It improves the experience on every imaginable front and makes it a whole lot more enjoyable. Spartans - deploy!

Thinking about it, I guess the point I'm making is...
 
...having to unlock higher difficulty settings instead of having access to them right away.
 
Halo : Reach makes a way better impression on Normal difficulty than it does on Heroic or Legendary.

Have to completely agree with you. 
 
 I completed my first playthrough solo on Normal and really enjoyed it and I think with all the changes they made to the gameplay mechanics playing on normal sets you up to work on the harder difficulty levels much better than jumping in from playing Halo 3 or ODST. 

So your saying that the hardest difficulty is hard. I have no idea why you would make your first play through the Legendary one that just seems silly. 
 
Also you seem to be making a lot of Halo Reach threads.

I think Heroic is excellently paced. I only die a couple times during a mission and the elites have enough health to be a challenge.   
It could all depend on the player's play style
I tend to play very carefully. Staying back and picking my targets. 

 
I agree. I also played thru it on Normal first and loved every second of it. I then played thru it on Heroic and it was definately more challenging and I didnt get the same flow thru the whole game like on Normal. Now im trying Legendary and its just a completely different game. I need to stay behind cover 90% of the time. Duck out to shoot and then back down to let my shield recover. I just took out the first two hunters and it was a nightmare hehe.