I could probably use the same quotes to support my stance, as there is no explicit statement that we should pray to the saints (and I do understand the difference in the usage of the word “pray” here, so I’m not implying idolatry).In Revelation 6:9-11, we see how those martyred for the faith are under the altar in heaven and are asking how long before God avenges their blood on the inhabitants of the earth. So it would seem that the saints in heaven are aware of events on earth. Also, later on in Ch. 8 verse 3, we are told that an angel offers incense (the prayers of all the holy ones) at the altar.
So, yes, it does seem to me that they can hear our prayers while in heaven.
Jon