The new facility is obviously really nice. Pretty much every physical seat is in the shade, which makes a huge difference. We went to a Cubs game vs the Giants in Scottsdale with no shade whatsoever and it was brutal even though it was still upper 70's/low 80's. In the shade at Cubs Park, it almost felt cold. They've got a lot of Wrigley elements like the stadium lights, scoreboard clock, and bricks behind home, but no evidence of ivy yet. We didn't eat much at the games there, but I was disappointed that they didn't have the Wrigley bison dogs. There's lots of ads in the park for Portillo's and Giordano's, but I didn't see either one actually available in the park. They did have an intersecting selection of food trucks parked in RF that were different each game.
As far as player accessibility, Ryan Braun actually signed for a lot of Brewer fans before the game (and of course got a ton of boo's/PED talk at each AB). Other than a couple fringe AAA type guys, none of the Cubs players were signing anything pregame. But post game, the Cubs' dugout tunnel opens up right next to the home plate gates and they walk several hundred yards to the clubhouse facility (aka "Under Armour Performance Center"). Guys like Kris Bryant, Albert Almora, and Brett Jackson were stopping to sign and chat with people. If you were out there in the 6th or 7th, you could probably have done the same with the starters as they left.
I was told the practice fields weren't yet open to the public because construction wasn't totally complete, and I didn't bother wandering over to check for myself...
I'll try to post a few exterior shots of the park and maybe a panoramic or 2, but here's a few from my seat and walking around the first day... (I went ahead and posted the large ones just because it's the Cubs thread and I can)
Section 116, Row 13, Seat 10 (almost exact center of the section)
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RF line
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LF line