Best: Modern Controller Layouts. I feel that the best controller layout started with the Genesis game pad and was further improved with the SNES game pad. For the SNES aside from the aforementioned D-pad you also have the four buttons that are layed out according to the angle of your right thumb. This made playing games much, much more comfortable. Later controller designs tried to improve by innovating but I feel they weren't successful (N64 and Gamecube pads to name a couple). To this day on almost every system the cross-button layout is used; the XBOX pad, the PS 1, 2, 3 and 4 pads, handheld pads, etc. It just works well and is comfortable and that's all anyone really ever needs.
Worst: The Internet. Keep in mind I'm not dissing the internet in general, but the fact that gaming quality has become lazy due to its existence. The best word I can come up with for this laziness is (drum roll): DLC. Yes,
Down
loadable
content has become the bane of modern gaming. Game producing scedules are becoming more and more tight as well as the budget that's offered to make them. Nowadays developers are looking to the internet to make their jobs easier in a very cheap way. If a game isn't complete? No problem! The internet will save the day! Ugh!! How many games have been release with bugs galore, incomplete stages, half-assed/unfinished story telling...the list goes on and on. It's just stupid. It's so lazy it's stupid. Back in the day companies worked hard to produce the best quality games anyone could buy or want to buy. If a game had leftover ideas that didn't make it into the final cut? That's what sequels were for. I just can't stress enough that virtually all gaming companies out there are relying on DLC to finish their products when they
SHOULD have been finished
BEFORE they left the development studio. Once more it's all about money and using cheap ways to save money
Worst: Quick time events. There's nothing interesting, exciting, innovative or fun about reducing your gameplay into finger aching versions of electronic simon says. As Yahtzee Crowshaw once quipped it's not a challenge, it's just "punishing old people".
I would have mentioned this but you beat me to it