If you go back and forth between Premiere and AE, you should use lossless compression or you’ll start geting visual artifacts that look jagged and change color. Interpret fields lower for SD-DV. AE has better raster fonts I think, plus a better deinterlacer. Lossless good outputs are TIFF, PSD, for image sequences, and animation or jpeg2000 for video. I personally use JPX, PSD or TIFF, they keep perfect, and I mean down to 3200% pixel RGB perfect encodes at 16 bpc. Targas are the safest though for multiple cpu’s and PNG’s cause gamma shifting and crashes.
AE would be hard to edit with, so I’d go with Premiere for that. If you plan on editing the whole thing finished and then deshake, you could wind up with problems tracking if you add effects, blur, or pretty much anything that de-contrasted and/or de-sharpened your footage(add temp adjustment to increase both). AE needs that badly for an accurate track which would require another export of unmodified footage to track off of anyway,
I would personally edit the rough cut in Premiere, leaving out the visual effects then de-shake and add special effects in AE or re-import back into Premiere again for final cut editing using SD-TV color management all the way.