How happy you are with the airline depends in large part on your priorities and flying pattern.
If, like me and my wife, your primary interest is in lie-flat TPACs and TATLs under $2-$3k RT, and if like us you have no problems redeeming your GPUs (or using miles + copay), then you're likely to be a relatively happy camper with United. Delta only gives 4 SWUs and requires an extra 25k BIS to get them. AAs SWU policy is more generous than United's, but their TPAC schedules (from where we fly) are not an attractive option and their international fleet is not fully lie-flat in C.
And we have been able to find attractive P and Z fares both to Central America and Europe. We're essentially budget C flyers and on about 70 segments this year only sat in Y (where C or F was offered) on a few short hops intra-Europe (where C is a joke) and 3 domestic segments.
We represent a very particular segment though: primarily (flexible) international flyers for whom domestic flights are not that important. CPUs? We don't care. Since we have to connect to go almost anywhere we usually don't have a domestic flight over 3.5 hours. If sitting in front matters we pay for F (if there is F). RPUs? We give them to friends or family. RJs? For two or three hour flights we don't care except insofar as they seem more subject to delays than mainline (and that is a problem). Food? We don't fly airlines for a gourmet experience (in fact while in the air my wife never eats and will only drink water).
The PQD requirements aren't a problem. The RDM changes will have little effect on us. IRROPS handling? Our experience has been relatively good although I believe it would have been much worse were I not able to feed the agents information. (In the last 300,000 miles, only once did we arrive more than three hours late.)
So while I don't consider us to be UA loyalists (or apologists), for us they remain the best option.