K.I.S.S. and think of the other 8 months : designers and AHJs read this !
2018.11.02 2130hrs please don't spend any more time on this .. keep it simple .. consider the other 3 seasons .. if you like to draw as much as you do (and I do, I'm an architect) consider a winter setting with snow and salt .. lose the grass idea - this is as urban a setting as there is and not enough space to make grass work without extensive maintenance (I can see all of the snow fence and T-poles around the grass every spring) .. embrace your nearby Dog training facility and think of this as another great place for them to train (using a variety of hard surfaces) .. make sure you use all Universal Design and CPTED principles .. using passive heating under hard surfaces to eliminate the need for harsh salts and eliminate ice and slippery surfaces (hence, reduce your personal injury lawsuits) .. be innovative but not experimental - read this - actually read this and Just Get On with It! (also, if yo have good designers they'll know about https://www.urbandesignmentalhealth.com/ God forbid you miss out on this! And, another 'for God's Sake, please do NOT make this a recognition of land use from the 1600s or before OR add some gender balance features - thanks! ps. remember AODA!