Revert "Revert recent coin selection changes"

Summary:
This reverts the revert commit 85f266319f586634df631a7438ffa6892aabeb9a

This patch re-applies D7674 and D7691 which were reverted in D7729 due to breakages on master (TSAN + flakiness across all builds).
Now that we've backported a number of changes that fix the instability issues, it's time to try applying these patches again.

This patch also includes a one-line addition to accommodate D7848.

Test Plan:

ninja check check-functional

Run TSAN in CI

Reviewers: #bitcoin_abc, deadalnix

Reviewed By: #bitcoin_abc, deadalnix

Subscribers: deadalnix

Differential Revision: https://reviews.bitcoinabc.org/D8015