I think there are several differences between heroic and paragon play.
*Paragon characters are much more durable and can in general go on for longer.
*Paragon characters have many more tricks up their sleeves. They will surprise you at times.
*Rituals really begin to become interesting, and they can by now gather a lot of intel without moving around. And a lot of other stuff too.
This is from a player point of view I guess. For a DM, the main difference is that the monsters get more hitpoints and nastier powers (save -twice- or die) are introduced.
But it my campaign, the biggest difference has definitely been the tone of the campaign. Now, I can't say it will work for other people, but for us (we evaluate a lot) it has been the nr1 thing that differentiated the paragon from the heroic tier.
As an example, there is a recap of my campaign in bullet points below:
Heroic tier
- Discover the ring of slavers operating out of their home town
- Infiltrate one of their HQ's and by accident release something from the Shadowfell
- Make new alliances for their hometown
- Kill some witches in a swamp and watch a church disappear along with a friend (?) into the Feywild
- Follow the paper trail and discover the gnolls running the slave operation
- Get captured and sold as slaves
- Win their freedom by winning an arena competition
- Destroy most of the gnoll slavers and their demon allies
- Enter the feywild in search of a friend - or is it a foe?
- Stumble over a troll invasion in the Feywild
Paragon Tier
- Lead the defense of the eladrin town against the troll armies
- Infiltrate the troll-home and afterwards the Feydark and kill (3 times!) the troll-king and liberate their friend.
- Be hailed as heroes of the Feywild and their hometown (which is where the troll army was heading afterwards)
- Become nobles
- Learn that the aspect of Yeenoghu (which was what was released from the Shadowfell early on in the campaign) is assembling a horde of gnolls and demons and intend to head their way.
- Return to the mortal world and take charge of their town (and fiefdom) as new noble of the realms.
- Create visionary tax-breaks for the common man in order to attrack more business to their town.
- Start building a church for Kord in said town.
- Stop the magical plague that is killing their towns-men by travelling to an ancient primordial temple and taking the ritual from the dead hands of a lich and then killing the dracolich that is spreading the magical plague.
- Track down the assassins who killed the high priest of Kord
- Participate in the decision making process of choosing a new high priest of Kord, all while foiling a demon attack on their own manor, the goal being to secure one of the few portal areas near the home town.
- Get trapped in a timeloop (1500 years back in time) in a battle between far realm's warped creatures led by a mad beholder and the dragonborn Tiamat-worshipers. Ends when the heroes kill the aspect of Tiamat
- Prepare and run the war preparations.
- Strike a deal with Bane and with the Eladrin of the Feywild for support in the coming war.
- Lead 30.000 men against 50.000 gnolls and demons in the Battles of Devil's Pass and winning the war.
- Be even bigger heroes
- Discover that the gods are not the real gods and that their fate is to kill the usurper gods - at least according to Bane and Asmodeus.
- Head to Sigil to find a 3000 year old vampire - and strike a deal with him
- Find a dungeon located under 2 miles of water, enter the dungeon and kill the demilich, thus acquiring one half of the ritual that will allow the heroes to enter the memories and mind of Kord.
I hope that the feel in tone and style is apparent. The players feel their influence on the world. They basically feel like VIP's now, which they certainly didn't at lower levels. I am gonna throw in a soccer analogy, even though I am guessing most people might not get it
Heroic tier is like Premier League - lots of interesting things happen, but in the end, nothing *that* important. Paragon tier is like Champions League, lots of interesting and very important matches that will shape the face of football for a while. Epic tier is more like the world cup final, every single day. You are just that important and what you do will affect millions of people.