Lively, fast & open sounding integrated under 3k?

no2
forward soundstage (begins at the listening position and extends beyond the speakers)

I have no idea what this means, and I’ve never experienced a soundstage that begins at the listening position — except with headphones. 

I would look at the Musical Fidelity M6si.  Doesn't quite double into 4 ohms but it is comfortable driving speakers with lower impedance.  

Lively sound that will be forward without being bright.  It is a dual mono design though it doesn't have two power supplies.  Made in Taiwan which is why it is relatively inexpensive.  In that price range it would be my first choice.  

A buddy of mine has the Krell and is pretty happy with it.  It replaced a Nord.  He loves it and it should deliver on what you are looking for.  

I haven't heard the other three and have no POV.  

I am an MF dealer.  PM me if you are interested.  

I was thinking Musical Fidelity also based on what you are looking for

I don't think I would recommend the Krell s300i integrated for this scenario.  The Krell really smooths the highs and it's not as open as others.

Music Fidelity would be a good candidate.  I would also look at Hegel integrateds and even Yamaha integrateds.  Those are both very fast and high resolution.

Thank you auxinput.

Btw. The 3.5ohm are a mistake. I have learned my speakers have a minimum of 5.3ohms with a maximum of 50ohms. So tube amps are a possibility as well. I have a eye on the 17W (in 8 and 4 ohm) quad va-one ei84 Push pull amp.