Has StudioLive 32R got delay on each input channel like outputs?
Yes. The Series III Racks are essentially exactly the same as the Series III Consoles under the hood, so all regular input channels 1-32 have Delay available on the input.
Can I assign an input source to more preamps on the desk?
I'm not sure I follow exactly what your question is, but if you mean can you do soft patching, so that the same physical input/preamp is sent to multiple DSP mixing channels, then no, that is currently not possible. It may be added in a future feature update though.