Wow! This thread just keeps growing!
Since we're 20 pages long now, it's hard to find all those nice quotes... so I'll just add my 2 cents at [MENTION=59096]thecasualoblivion[/MENTION] original post:
Know that when you say you're a selfish player, you're not making things easier for you

!
Anyway... may I ask more details about what and how you played?! How you're being "coward" and "letting other people take 5E's randomness to the face"?
Defenders in 4E were more sticky, and also different from traditional D&D defenders - they were a lot more video game-y with Mark and stuff.
In 5e we're back to "classes being classes" and not "classes being an approach to roles".
Anyway, I have a very different experience with 5e than you: I play a Fighter, Sword & Shield with Heavy Armor Mastery feat. I feel a lot more resistant than the rest of the party in most combats, except for my Barbarian Bear Totem friend who's basically indestructible - he justs jump in the middle of the fray, get hit every time and hardly drops.
When combats are shorter, evey inch of improvement counts. In that sense, it's harder to gauge 5e abilities and builds than 4e - while in 4e you knew most of times when something was effective right after reading it, in 5e there are things you must see in play to know if it's that above the cut, it's just normal or if it sucks.
Sometimes I like to play the support... but I know the feeling. I had a hard time liking Leader classes in 4e (even thought I liked to play a Sivis Bard once).
But since we don't have roles anymore, evey class can "shine". Even the Bard isn't a pure supporter anymore - you might as well play a Bard Gish, or even DPS focus with access to Ranger and Paladin spells way before expected level.
You're right, but mostly because:
A) We don't have as may options as we in 3.5 and 4E
B) We don't have as many trap options as we had (thanks to Bounded Accuracy and other design approachs)
But there are still "combos", even defensive ones - they are usually more splicit than they used to be (because A and B).
Well, I don't have a feeling that Spellcasters were any special in 4E.
I've seen spellcasters change the tide of battles in the first few levels with their lonly spells. A well placed Sleep makes wonders.
As in 4e, a lot depends on the frequency of combats. At low levels you have few 1st / 2nd level spels (or Daily). If you fight one or two fights a day, you can use more of those powers per fight. Same with frequency of short rests.
Anyway...
About "kicking ass" - when I play I want my characters to "shine". That means when I play a "Striker" he must kick ass. But when I play a skill monkey, party face more of a support character (we can't have it all), that means carrying the team throught interactions and skill challanges.
In that sense we may have something in common, and in the games I played in 5e I always had a chance to shine (most times with my Fighter, but also played a couple sessions as bard).