I’ve never had a problem with an excess balance with suica. It’s so widely accepted now you’ll find a way to use the last bit - you can use it to buy duty free in the airport if you are stuck with some. Given they now sell Noguchi naohiko sake at Haneda, there’s a good reason to go shopping there.

TBF I’m never that worried about having an excess balance as I know I’ll be back soon

as for the other questions

theres no way of charging a physical suica or pasmo with a credit card.

As for loosing the balance if you loose your phone - with a max top up of 20man your phone is the bigger concern.

why suica and not pasmo - you can earn jre points with suica, probably not that much of an advantage unless you shop a lot in jr stations or buy Shinkansen tickets on eki-net but it’s basically 1-2% cash back when you do. I spend enough in kimijimaya liquors ebisu station when I’m in Tokyo to score a free lunch most trips.

a good reason to have either is you can currently get a good discount on Shinkansen tickets if you load them on to an IC card rather than get paper tickets.