The big one is the what... 20 minute adventure day ? Rules as written yes, this "theoretically" could be a problem. The thing is , I have been running campaigns for about 15 years now and I can honestly say I have never had this problem. This brings me to my question, does this ACTUALLY happen in your games? If so, why do you allow it?
Yes, it was a big feature of my Rolemaster campaigns. And the reason that I "allowed" it was because I play a game in which it is the prerogative of the players to make choices and act on them.
The other thing is the so called "Caster / Melee" rift. Where wizards and other casters are basically much better than every one else. Has anyone ever actually encountered this in their games?
Yes - I've encountered it in AD&D and in Rolemaster.
it just seems to me that given RPG's that have so many rules these type of things are bound to happen
I don't agree with this. My group tweaked RM in varius ways to make caster's less dominant. It worked. And I haven't found this issue in 4e.
In my opinion characters need some sort of drawback, in the form of ability scores or powers or whatever.
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In my opinion, all characters should have drawbacks
I'm indifferent to drawbacks. I think that PCs should face adversity. But there are a lot of different ways that can be done, and a lot of ways the mechanics can feed into that.
Here is a story that links the 15-minute day to drawbacks: in one of my RM games, the PCs were all wizards, and all but one was a meditation expert, meaning that they could recover their spell points even more quickly. The one who was not a meditation expert therefore looked for an alternative way to start regaining spell points quickly, and hit upon an enchanted herb called "hugar". Unfortunately, hugar is both expensive and highly addictive (RM uses a mechanic called "addication factors", and has mechanics for withdrawal as well) and the PC ended up losing his house, his job, his dignity etc, and eventually sold out his home town to a rival empire in return for a promise of house and (better) job back.
No one playing knew in advance that failure to have a strong meditation skill would turn out to be such a signficant element in character or plot development.
that's where the DM comes in. The DM is there to be a referee, he is there to reign in things that may be game breaking. The DM should not allow free reign in their game letting players get what ever they want.
This is one way of thinking about the GM's role. It's not my preferred approach. I prefer to follow the lead of the players in building and playing their PCs, and to present situations that oblige those PCs, and therefore the players, to make choices. What choices they make are up to them.