1) A table showing which surfaces have which speeds. This can be found by randomly clicking around the training center and writing down the results, which I didn't discover until my third time through the demo. For those of us who know little about tennis, this information could be very useful. (For example, I had assumed that 'cement' was the fastest surface and 'grass' was average.)
2) A description of what the effects of the Coach talents are, similar to your current explanation of the Player talents.
a) What does it mean to have a +15% 'physiotherapy' rating? Does it reduce injury chance? Does it shorten injury durations? Does it affect rate at which fatigue and form are recovered, or does 'physical' do that?
b) How does the potential detection talent work? I can't figure out how to get a look at the character page for players I might like to contract with. I can only find their tournament results, which means little to me because it doesn't tell me what level of tournament she has been competing in.
c) What is the use of spending more than one star oon charisma? I have never been turned down by a trainer, even when I had no charisma. Do more trainers appear on the list? Do they work less expensively?
d) Has anyone found the luck talent to be of any use? I have never tried it, but if it only affect the first round, it woould seem to be a waste of stars. First round matchups have been the least of my worries.…
3) It costs money to drag trainers, sparring partners and assistant around the world, but the best I can tell, coaches come along for free. Is that right, or am I missing something? Certainly it should cost money to fly the coach and put him up in a room for a week. And while I'm on the subject, if you fly home as soon as you get bounced from a tournament, why do you have to pay for the full week? First round exits should save money.
4) On a related topic, I think that style of travel and quality of lodgings should have an effect on fatigue. Taking business class travel and three star hotels as the norm, I suggest that players who fly coach should incur somewhat greater travel fatigue and those flying luxury somewhat less. Likewise, players staying in five star hotels (with jacuzzi, sauna, in-room massage therapist) should recover fatigue between rounds more quickly, while those in one star flea bags are kept up late listening to the porn film playing in the next room and should recover less. (Including the massage therapist and porn film in the game would need to wait until the next generation of the game — with 3D graphics — is released.)

5) I have a question: When a player flies with her coach immediately back to the training center after a tournament and has some hours of traing left that week, why does the game engine tell her that the coach isn't with her at the center? They flew together, so if she's there, shouldn't he be also? But he doesn't show up until the beginning of the next week. As a result of that, I have gotten into the habit of remaining at the tournament site until the end of the week so I can get more training in, which seems perverse.
6) Other than that, I am going to add my vote for mixed doubles. A most excellent game.