There were a few new instructions, too, mostly closing holes. You could left or right shift with a constant, while the 8086 had only 1 or the CX register. I think mul also gained a constant.
The fact that Intel released a CPU that could not be put in a PC probably indicates how low they estimated the survivability of the PC.
In the x86 microarchitectures superscalar came in Pentium and OoO got introduced in Pentium Pro.
(Superscalar is just having >1 pipelines, which at its introduction meant needing to manually schedule your code very carefully to take advantage of it absent the OoO execution. For example the frequently posted-about Doom optimizations and talk of the u and v pipes are about this. The scheduling didn't happen transparently in early superscalars, at best the cpu automatically stalled, and some archs (eg MIPS, i860, TI C3x) even visibly punted hardware detection of pipeline hazards and required the code to just not go there, see load delay slots and branch delay slots. )