I'd be open to hearing how you've handled certain things over the years. With those success rates over that length of time, it sounds as though I could learn how to improve what I'm doing.
I remember being in 3.5 games in which the guy playing the wizard would intentionally not do anything during the first round of combat; he'd do so as a courtesy to the rest of us so that other people would get a chance to play the game. Outside of combat? The same character easily handled problems in other pillars as well. .
Angel summoner/BMX bandit is usually the first example people give of imbalanced PC classes, and I will admit I only played 3e off and on (I stuck with AD&D). That being said, what I've found almost exclusively in these scenarios is that certain parts of the game are glossed over in the favor of the caster. Notably things like preparing spells, components, and spell interruption. Even in 3e, you still can only prepare a limited number of spells (unless you were a sorcerer, in which you were limited in other ways on spell choice). There is no way a player can prepare the perfect spells for all of the scenarios in that session. Their PC simply doesn't have enough slots to learn all the perfect combat spells and interaction spells and exploration spells, let alone how would the player know what to prepare. Then even if they did, do they have all or the required components? And do the monsters ever attack him or her when casting a spell in combat to interrupt them? And how does the player know how many encounters are going to be expected (meaning, how do they know how many spells they can cast that encounter and how many should they keep in reserve due to the unknown)? IME, what I've seen is parties cater to the caster's needs even if it goes against the natural flow of the game. I.e., "Well, we need to rest because I blew all of my spells." If you're doing that, then no wonder casters seem so powerful, because you're placing them as more important as anyone else by catering to them. Not to mention another thing I see a lot: PCs being able to rest whenever they want, AKA the DM pausing the game world when PCs decide to rest, which shouldn't happen.
From what I know of your brief scenario, what I have seen almost always happen is that the player is using out of character knowledge to know what they are going to expect during that session that their PC never would, and selects spells based on that. *OR*, they ignore spell prep altogether and cast from their entire list of spells. They also demand the party cater to their resting needs as well, and almost never use components or spell interruption.
I don't play 4e, so I can't comment on that. However, I hear a lot how 4e was the most balanced game mechanically, so I imagine there aren't a lot of people claiming it's game breaking.
Definitely not "minor" differences at all.
There are combinations in 5e that can really outshine other classes. This particular character was a Greenflame Blade Bladesong / Arcane Trickster who ended up with nearly advantage in every attack, damage in the 40-50 range at around level 11 from basic attacks, best AC in the group, and 20+ Minimum rolls on a ton of skills due to Rogue abilities, not to mention survivability and manoeuvrability that comes from cunning action, improved evasion, uncanny dodge, etc. He was the best combat character, the best exploration character, and pretty darn good social as well. He is also a DM who knows the rules inside and out and purposely set out to make a broken character reasons I won't go into.
He outshone a lot of us by more than just +1 or +2 mate, he was doing 3-4 times more damage than my War Cleric as example, and it caused a lot of angst between players and the DM.
All this was Raw, legit, perfectly within the rules. No homebrew, wotc official module, official books.
There are other combinations as well that can be problematic. We've had a character go from about 20-30 DPD to over 90DPR spread out over three rounds at levels 11-14 (Fighter/Rogue Assassin) when he took sharpshooter somewhere around level 12+.
He trivialised the poor DMs climatic dragon fights in Tyranny of Dragons, since without modification they're not equipped to handle this kind of firepower. Greater invisibility (from the Bard) plus sharpshooter plus haste (from the Sorcerer) from extreme range = good night.
Yes, you can "DM" around these things but after a certain point you're just putting a band aid solution over something that's inherently broken in the game, and in my games there are certain house rules to certain classes and feats because of this.
IME, whenever someone has to wait until level 11, or 12, or whatever to reach their "uber build", they are lacking quite a bit all the way up until that point because while everyone else is getting extra feats, attacks, etc, they are still struggling to get to their multiclass requirements. And since playing from level 1 to level 12 is the largest amount of time most gamers play, I don't see huge issues with someone being behind everyone else for 75% of their gaming to be better at 25% of their gaming time. Similar to AD&D and magic users.
That all being said, without knowing more exact details, PCs that are built towards maximizing DPR are much weaker in other areas. So if your style is to focus on combat way more than any other pillar, it's no wonder why the combat DPR build seems to be overpowered. I don't know their exact builds, but I'd be curious to know why they could be so much better at interaction as well as everything else over every other PC. Your cleric should be way better as things like WIS saves and battlefield control.
Also, like I replied in this post above, it seems as though the party is catering to that player. That PC requires the bard to cast spells on him, and the sorcerer to cast spells on him, etc. I'm guessing you probably also rest when that player says, "Well, I'm out of my bonus AC uses for my bladesinger ability." When you're catering to a PC, and the other PCs are buffing him, that's not really a balance problem of the mechanics. That's a behavior issue of the players. I.e., you're
choosing to make him super uber by helping him out. Nothing wrong with that of course if that's the tactics you want, but you can't really get upset at a problem that you had a hand in creating yourself as a group.
