Hello everyone,I need all of your technical expertise.Be gentle,semi-nube here

Looking to upgrade my 22 year old system

.Fisher dual amp set up,one is receiver one is surround amp.

.Matching fisher speakers.120 watts per channel.
Room layout is "L" shaped.Rectangular aspect is 21'6"L x 11'6"W x 7'3" H.
ELL ext. is 7' x 6'6" W x 7'3" H.Stairway is here.
Floor is fully carpeted,walls are drywall with some paneling,drop ceiling with regular tiles(2'x4').
Questions(I have many)BTW $3000 for speakers,(mains,center and sub).I will be going the SVS route on the sub.I am an hour from their factory

can pick up myself.Haven't decided on speakers yet, have to go audition.
Pre/pro-Emotivas UMC-1 or Integras DHC-40.1-I won't purchase Emotiva until they address all the bugs that are manifesting themselves.
Your thoughts and opinions on these two units.I looked at the rotel 15 series but its a litttle more than I care to spend.(Why so expensive?)
What would I gain with these 2 units,what would I lose in comparison?
I plan on a 5.1 set up right now and would use the surround speakers I have now.7.1 later on.
I will also be purchasing Emotivas XPA-5 amp.
If and when I go to 7.1,wouldn't it be better to go with an onkyo 876 so I can drive the front stage with the XPA and the rest with the receiver as it does have pre outs?Is 7.1 feasible for the room size?
Would this set up be overkill for the room dimensions?
With the system I have now I can knock pictures off the wall at half volume.
I like the internet aspect of the DHC and would like a system that would be easily expandable.
Very knowledgeable people posting on these forums,I thank you in advance for your input, knowledge and expertise.
Len