In the sticky - permanent - posts on this site are contrarian23's essays on pitcher fatigue. I strongly suggest reading them. Also anything by Elbirdo on pitch counts - see the first page of this thread. 1300 is probably a little more IP than you need in an OL, I agree with Mixtroy, though his particular daring approach to rotations is not one I have tried.
The 90-100 pitch count is just a fashion in real world baseball, and instead here you really need to set pitch counts.
If you don't want to do the math, the simple version is 15 pitches per IP/162 plus the 10% bonus WIS gives each pitcher divided by the number of starts expected (40 in a four man rotation, 54 in a three man rotation, 32-3 in a five man rotation) once the team has been created, but you need to vary that for IP/G. In general if IP/G times 15 pitches is lower than what the above calculation got you, or vice versa, then the minimum pitch count is usually the lower number of those two (IP/162 plus 10% times 15 divided by number of expected starts, versus IP/G times 15) and the higher the maximum pitch count for that pitcher. Some people use 16.5 pitches per inning instead of 15, though that works better for more modern pitchers or ones with more strikeouts.
But for some deadball era pitchers, it is better to calculate a little lower - 13 or 14 pitches per inning as for Addie Joss, since otherwise they will got too many innings since they don't strike out a lot of people, nor walk nor give up many hits.
But the best way to calculate all this is the long version, which I am usually too lazy to use, which you will find from those two sources and experts on pitching that i cited above. Good luck. ozomati is right that in general parks don't matter for setting pitch counts, they matter for the number of IP overall on the staff, but mainly Coors and a couple of others, while some pitcher's parks mean you can get away with a bit fewer IP. That is a different question than pitch counts though.
3/19/2017 8:29 PM (edited)