Quite often, whether as a result of the game crash crashing or a loss of internet, a player will be disconnected for the picking phase of a game and end up randoming a hero. This can be difficult for both the player and their team to deal with. While I don't believe adding a pause function to the picking stage is viable, I think there are a few ways that the negative effects of this could be mitigated:
1. In the options menu have "Allow team pick" which allows team-mates to indicate a pick for you if you haven't already (i.e. this does not over-ride any indications you have given). This might need to be limited to buddies to avoid team-mates fighting over an absentee's pick.
2. Allow hero swapping in-game up to the 0 minute mark (so you can pause for a team-member to return and adjust if they're not comfortable with their hero). This might need to be disabled in tournament mode.
3. Allow avatar changing in-game up to the 0 minute mark (in case you have an alt for the hero you ended up with but weren't there to pick it. Also in case you had the avatar but forgot to pick it).
i like options 1 and 2, i think 3 is a bit irrelevant but if you like it's fine as far as i'm
another suggestion i've seen around to fix this and which i find pretty good: in herodex or options, you could select a 1st and 2nd option of heroes in case you disconnect. that being, if you're disconnected at the end of the picking phase, your first option will be chosen for you, or if it's already the taken then the second option (if both are taken then you random).