...about getting the pianos right first:
ATTACKS - the only thing I've discovered is that I can't get rid of obnoxious hammer noise on some notes. It looks like there is some cross modeling/sampling going on there between the fundamental and the noise sample/model which makes editing to perfection, impossible. Even when you lower the hammer noise to minimum and just listen to the fundamental... it is too percussive and sounds like the hammer noise is still there.
But if you're hearing something wrong with the attacks in general, or don't think there's enough of an attack... I would take a look at your DAC. We recently conducted a mastering DAC comparison (everything under $5k) and found huge differences in transient reproduction when going from a $700 DAC to a $2500 DAC. RME's under $2k tend to compress transients/attacks a little whereas a Bench Mark DAC yields a very clear and delightful piano note attack... night and day between the two. I have everything here in the studio from Apogees, Rolands, Lynx, EMM Labs and I use the Lynx Hilo when playing Live. If your budget doesn't allow improvement on that front... then rev the pianos up to 96K and you will get considerable improvement. I have run mine at (internal speed) 192k but I can't find a processor that can handle a full down the piano gliss with the pedal down. The system belches, PT overloads and cuts out for a second and so I had to drop back to 96k/24bit.
But I do agree with you about getting the pianos right. The stock renderings of these pianos (all of them), are just not there yet because they are models left without enough tedious editing to make them stunning. This is the same issue with monster memory VST pianos... no one's doing the hard work. Not enough work has been done to make the PT pianos playable at concert volumes without ripping someone's head off. That being said, there are few people knowledgeable and willing to do that tedious work.
The Steinway, Bluethner, even the K2, can be molded into gorgeous instruments but it takes time, infinite patience, and a combination of science and art... not to mention a learning curve to understand the PT software. The other PT pianos require too much work to get them to the same standard but they are still useful for special apps. If I purchased PT with the edited models I'm using... it would've saved months of work and that's the level of work I used to spend on the digital pianos I designed for artists all over the world... from scratch.
At one point, I thought about having to lug a laptop with all the weirdnesses and the cables, the DAC and interfaces on the job... versus having an all in the box solution. So I bought a Roland RD800 and the Yamaha CP4 figuring I would find one or the other would be best... but neither is the best. The Roland suffers from an non-adjustable, unnaturally short decay and the Yamaha sounds beautiful on stage but playing it convincingly soft is just not in the cards. If I didn't have the PT pianos prepared and ready, I would have been very frustrated with these keyboards. So, all the hard editing work was not only worth it but it was the only option to having a magnificent instrument to play that responds perfectly and predictably to every nuance when exposed solo, with demanding passages played delicately soft, and at concert volume. Incredible.
