As posted logs doesn’t shows malware activity, I think that there is no need to go to extra checks.

My laptop is now running normally, but the avast! service is still disabled under msconfig, as it was preventing me from booting my laptop. Should I now attempt to re-enable this service?

Can’t tell. I am not member of avast team, therefore I can’t assist you in that. I would re-try.

Before you try to enable, create few system restore points.

You can remove OTL by clicking on CleanUp! button.