DK64 was originally intended to be like the DKC series having the partners and everything but because those mechanics didn't quite work they decided to make it similar to Banjo Kazooie but also keep many DKC elements.
Also Rare's games were still fantastic around that era look at all their N64 games, genious. Diddy Kong Racing is my second favourite racing game of all time (my favourite being MK64 gotta love that Moo Moo Farm
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) and Goldeneye being one of the few FPS games I enjoy. Even on the gamecube Starfox Adventures was fun, not as a starfox game but as a platformer. Donkey Kong Racing also looked really good.
During their XBOX years they did slip a bit with Grabbed by the Ghoulies (fun but not a great XBOX game) and I didn't really like Conker Live and Reloaded as much as BFD. But with the 360 and VP they have made a huge improvement and they are back to the high calibour games that we all know and love from Rare, so I can at least be sure that BK3 will be great.