It really depends on what the rules are like.
4E still has some glaring issues from my perspective:
1) No in combat scrolls. There should be a way to quickly cast a ritual like Knock in combat. Some of my fondest memories in earlier editions was when the party was in dire straits and a player pulled out an old dusty scroll that had been on his character sheet for 9 months and he saves the day with it.
2) One round durations. WotC said "Oh, a few PCs casting a few spells over the entire party for the encounter encounter is bad, instead we will have EVERY PC effectively cast spells over the entire party and/or the enemies for some fraction of a round". Effect durations end at the start of your next turn, the end of your next turn, the start of the foe's next turn, the end of the foe's next turn, after a save is made, or until the end of the encounter.
The problem here is the vast number of conditions on PCs and NPCs at any given time. We use little plastic rings that we put on the miniatures and we often have 20 or more of these rings out on the miniatures at any given time.
That's a LOT of bookkeeping. Every single creature's turn tends to result in little plastic rings either being put on some miniatures, or off of some miniatures. The game is all about condition tracking now.
We waste a lot of time in game figuring out exactly all of the modifiers to a given situation and tracking the changes of them.
3) Very few higher level At Will powers. For the most part, the dinky little At Wills learned at low level stick with the PC his entire life. Yawn. Paragon Level and Epic Level should add in a new cool At Will while maintaining the original Heroic At Wills. Learning new Encounter and Daily powers is fine, but only learning those is meh. The focus should be more on multiple At Wills and less on multiple Encounter and Dailies.
4) Limited balance of power sources. I really dislike the concept that "if the Wizard can do an area attack, the Fighter must be able to do an area attack". And not just with his sword. He can do things like Come and Get It where he somehow mystically forces his foes to move, even if they don't want to, from 15 feet away. I think the distinction between the power sources should be better defined. Sorry, but your Fighter just isn't going to heal himself and your Rogue isn't going to Teleport due to class powers.
Better expressed, I dislike magical effects in the Martial powers source. Rationals aside, having a dying PC suddenly jump up and be mostly whole and hearty because a Warlord ally across the room yelled "Get Up!" feels too much like magic to me.
I do not like the current entitlement system that all power sources are entitled to all types of effects. I think each power source should be special in it's own unique way. Divine should be the healers and supporters. Arcane should be the teleporters and multiple target damage dealers. Martial should be the single target damage dealers and focused on what the PC can personally do (climb, jump, attack, etc.), not what the PC can mystically do beyond himself (teleport, fly, fireball). The line is pretty darn blurry in 4E. As an example in 3E, when the Simbul healing spells first came out, it was lame. Wizards could now heal. Meh.
Granted, this sounds like a rant. It isn't. I just prefer segregation of abilities via power source.
5) More focus on non-attack powers. The vast majority of powers in the game system do damage. It would be nice if each player had more than just a few utility powers at his disposal. The ability to cast rituals with scrolls would help with this.
