Audio Damage make a nice flanger called Fluid. It's more on the over the top side of things but its useful for faux stereo widening. Try it on a send followed by some punching sidechain compression. We use it for pads, with the sidechain on them making for some groove. A touch of verb off the master verb send and it sits nicely deep in the mix.
Anyway the 505. Wow. I owned one in the 90's like a lot of people and used it in Soundforge as a makeshift transport control. Was a period when i was editing a lot of audio for university so it was useful. I guess people dont do that kind of thing anymore, with midi kb's often having transport controls mapped.
Anyway, you cant compare the shuffle on a 909 with, well, anything really. Comparing it to a digital drum machine even under the same X0X range is a bit odd. The whole shuffle thing though, its really what you want it to be. I have an MPC but write most of my beats in the DAW. If i want a certain feel to a beat then i turn off the grid and give it a nudge. Certainly nudging a tom hit a few ticks before a kick drum hit on the same note helps when it comes to the envelope on your compressor.