Perhaps we could try transportation between guild member with railway system with train animation
1x1 size for rail track, when rail track meets river/sea, replace with a bridge connect between land.
2x2 size for train station (Qty:1) Only accessible after build Guildhall.
Its purpose is (A) allow guild member to drop combat buff (e.g ballista, horseshoes) to destination
(B) drop/pull any troops (max limit is 1000) for reinforcement if user urgently needed.
Transport duration increase depend on amount of buff/troops send to user.