Yeah, interesting small features.
I was also checking 90K iPhone 7 Plus and it also did not have those features and your are complaining about 35K midranger.
That missed call timer tells how much time the other person kept calling you in that missed call.
If it says in missed call log, 'rang 13 times', it means the caller kept calling for 60 seconds, but you did not pick.
6 times means, 30 seconds.
3 times means, 15 seconds.
1 time means, kanjoos logon ki choti si 1 sec ki miscall k kahin doosra banda call pick na kar ley. Lol.
Now my friends and family know that if it's an urgent or important call, they will give me 60 seconds missed call in case if i don't pick. And then i will call back as quick as possible.
Rest, normally they call for around 30 seconds and then hang up for normal calls.
When i am busy, 75% of time, i don't pick calls or call back unless urgent and this little feature helps a lot in it.