The would be a good option. Even better perhaps, alternatively or additionally, would be to have comments appear in a collapsible* section - so you can view one line (with a popover option) or the whole comment, in context.
Hopefully, if long comments do become possible, it will be possible to view the whole comment in the Properties panel - ie in a large multi-line text box. The Mail Body field is resizable - perhaps the Comments field could be too.
(*Another two options for your right-click menu occur to me: Collapse All/Expand All.)