To me...the question here isn't the time spent, it is the mental impact to the DM.
During a busy combat, DMs are....very busy! You are tracking 5-10 monsters, adjudicating effects, looking up spells, recording damage, maybe you have some terrain effects, etc etc.
I can say that when I run combats like that...it is easy to forget the small things. Little bonuses here and there, etc.
So, does looking for save bonuses in multiple places have a mental impact? I think it does. In fact more likely than not what would happen to me is I get used to look at ability scores for saves...and forget about the save bonuses entirely.
Once again I will state...is this a BIG deal? Probably not...but I do agree it could have been done even better.
I personally think that after getting burnt a few times (if this is a problem for some DMs), most DMs will make this automatic and will probably not even think about it.
However, I do agree with you that they could have easily made it better. For example:
Code:
STR DEX CON INT WIS CHA
10 (+0) 10 (+0) 10 (+0/+2) 10 (+0) 14 (+2) 11 (+0)
where the first number under CON is the modifier and the second number is the save.