"Sounds powerful" is like saying "tastes cold" it's meaningless!
Any one of the receivers you mentioned are going to be able to produce their rated power output into the load specified. If the specs say something like: 110 W x 7, all channels driven into a 6 ohm load from 20 Hz- 20 kHz, then they'll absolutely produce that amount of power.
The only meaningful deviations from this would be if the ratings were taken with less than all channels driven, or if the power ratings were measured at 1 kHz into a 6 ohm load (or 8 ohm load) instead of the more meaningful 20 Hz- 20 kHz full-bandwidth ratings.
I can guarantee you that your Pioneer if performing to spec will absolutely deliver 90 w/ch
A vintage receiver may "sound more powerful" for a bunch of reasons
1. Different preamp sensitivity: you feed a 2V line level output into a vintage receiver, that's almost 4 times the amount of voltage your average 70s tape deck put out. As a result, the receiver is going to reach it's maximum power output that much faster. This explains the old "I turn my old receiver to 5 and it cranks...I have to turn by new one up to -1 or 0 to make it play as loud"
2. higher distortion. A distorted signal is going to sound louder than a clean signal. so that little 30W Pioneer SA-5200 with 1% THD is going to seem louder than a good clean 100W amplifier putting out similar power levels.
3. Gain structure: old receivers were pretty simple devices. the volume control started at "0" and could be rotated clockwise to "10". Under most conditions, raising that volume knob above 12 o'clock or so was going to create nothing but distortion and magic smoke. This is especially true with "hotter" modern sources like CD. Most new AV receivers on the other hand are designed so that their volume controls can be turned almost all the way up without creating a lot of noise and distortion. For instance, I run my Kenwood AV receiver at -5 dB to +3 dB almost all the time with my 87 dB efficient speakers...the volume control only goes up to +10 I think, so this seems quite high. It's not though, as the receiver has been designed to use the full range of its volume control without damage or significant distortion.
Just a few notes. Buy a good receiver with a robust power supply and the features you need. It's gonna rock.