Yet another - which tire thread!

Just got a new to me 2016 Scott Solace Premium, this is their "endurance" bike. I'm a big guy, its their XXL size, and it came GP5000 TL tires in 28. On the stock Syncros RP1.0, these tires currently measure 27.5mm. The bike will be used for commuting to work on nice days, casual weekend or evening rides, nothing competitive at all. 90% pavement, occasional dirt trail. Can I ride on gravel with wheels/tires like this without rising damage to the rims? Anyway, I am looking for a bigger tire and am thinking of the Schwalbe G-One TL. Their sizes are 30, 35, and 38. The GP5000s on it now will allow a 6mm allen wrench to pass between them and the bike, front and back at every point, currently. So I have approx 39.5mm of clearance (6 + 27.5 + 6).

First, IF they would fit, can I safely mount a 35mm tire on my RP1.0s? They (according to an online review) measure 21 outside and 15 inside. They come stock with 28 Duranos. Yes, I know with 35c tires any aero advantage would be negated, but I will not be racing, I'm just wondering if it is a safe setup?

Second, anyone know if the G-Ones are pretty true to size? If the 35s really are 35mm on my wheels, that would give just over 2mm clearance at the tightest point on each side. Good enough?

Thoughts?
I'm open to other suggestions, any other really good 32s I should look at?

Thanks in advance.