Should Abathur typically be left ot solo a lane, or does he require some kind of support?
Abathur's trait, locusts, are most effective when no one's countering his lane. In the beginning, help a solo laner against another solo laner for pushing. During objective time, switch to an empty lane (top lane in Blackheart's Bay when chests are spawned for example). Abathur pushes best when he's ignored. Therefore, an Abathur should relocate as much as he can for the optimal pushing and avoiding hunters such as Nova, Zeratul and Tyrande(owl).
What are the things to watch for on your own character given that Abathur can use abilities to enhance others?
Abathur has 2 major builds I'd say: teamfight build and backdoor pushing build. When Abathur goes teamfight build:
- After level 4, your attack speed is increased 25%. This means, you should keep auto attacking on certain situations with Illidan/Thrall or simply you can win almost every 1v1 when Abathurs symbiote is on you. So stay alert.
- When Abathur uses symbiote on you, be ready to engage as you are a 1.75 person now with the Abathur on you. His Q and W deals significant damage with talent upgrades (See lvl 1 and lvl 7 talents).
- After level 20, if Abathur takes Hivemind talent and goes symbiote on 2 targets. If symbiote is on you, try to stay close to the other symbiote host, so the second symbiote is not cancelled. This way, Abathur will have double the damage potential, and 2 of the teammates will have 25% increased attack speed. Pretty rad.
How do you need to compensate / account for an Abathur on your team for map objectives such as treasure chests and skulls?
In general, you should not fully commit to team fights when you have an Abathur in the team. You should always be more careful as you have only 4 players to target in a team fight, so it is easier to get nuked. Positioning is very important when Abathur is in your team. Play safer, try not to engage 5v5 too early and you'll not feel Abathur's body absence.
Is it necessary to check on Abathur's build and adjust your play style accordingly?
If Abathur player doesn't communicate, that is exactly what you should do. If he goes backdoor build, you have to be even more careful on team fights. Adapt a general hit and run strategy that game and let Abathur work his magic back door.
But, in short: how can you be a good team mate for Abathur in public matches?
Just don't engage like you are 5v5. Always communicate with teammates. Use pings on yourself if you need help from Abathur.