IPhone 5s Can't Imessage Some Phone Numbers Only ICloud

Proud user of apple devices for around 5 years, last week my iPhone 5s was not able to deliver an iMessage to an iPhone 5c, so it went as regular SMS text; and when I got a reply, it arrived from the iCloud id. Then, the exact same thing happened on Saturday with another friend using an iPhone 4 (no 4s).

Researching on internet, I read something that people have problem to activate the iMessage from their number and it appears grayed out in the settings, so they cannot select it.... I am able to send iMessages to other iPhones, but I still looked in my settings and my number is grayed out and I CANNOT deselect it (the opposite of what I read), so I still went through the solution proposed where I reset the network settings on my iPhone to factory. I not only lost all the passwords to the WiFi I had, but it didn't solve the issue.

I can not send iMessages to two contacts using their numbers. Additionally, the message history now is split in two in my device -which doesn't make sense as the number and iCloud id belong to the same person; doesn't it make sense that the history merge onto one contact name? It sure displays the name, not the id (phone number or iCloud address).

I assume this is a big flaw of iOS 8.1.1 as iMessages never failed this way for me, or at least that a good reset of the phone wouldn't fix. I found extremely ridiculous that now Apple says the solution is to jump through hoops and loops for a temporal solution. I still think Apple systems are more stable and reliable than the others; but I don't want to see the company start to conform with 'good for now' or 'good enough' operating systems.

PS My friend's iPhone 5s have problems to maintain wireless connections to play music in his own house, while the Apple computer works without issue.Â

Apple... are we going to get an new iOS for our phones to fix iMessages across devices?

Info:
iPhone 5s, iOS 8.1.1