I totally agree with Nana4Life about the drip tip colours. I have the soft touch titans, and really, not many drip tips match the battery colours. Tank colours don't really go either -which is why I use all white or clear tanks with coloured dts.
Lanyards, yes please. I flirted with Ego Twists for a while and got lanyards for those, they worked really well when driving. I have copied an idea from I think Mary K from ECF and have made my own lanyard attachment for my titans - working well. It'd be nice to have some spiffy lanyard options (and not just the very masculine leather pouches).
And yes, these things do matter for some people. These batteries are just so elegant that they make one want to team them with matching or co-ordinating accessories.
Aside from better colour co-ordination, one accessory I would love (and would be very difficult to do) would be a way to smooth the line between the titan battery and the tank.
For Egos, you can buy collars that screw into the outer threads, which flare out to meet the line of the tank and are available for both 3.5 & 6 ml tanks. This would be harder for KR808s because there's no outer thread and you don't want to block the air intake holes. Still, it would be nice to smooth out that line somehow. A girl can dream