I'd go with it as it sits now.  A few clicks of elevator trim will get things right soon enough.

And that was an excellent move on your part to extend the fuselage.  Looks and moment arms be damned, the advantages of removing that lead will easily make up for any other issues many times over.

By lengthening the nose you may already have corrected some of the ground twitchiness issues just by creating a longer swing length on the nose.  Also if the landing gear is located quite forward from the CG location this can lead to a lot of twitchiness in ground handling.  If you can see that the LG is quite forward and if it's possible to unbolt the gear and swing it around to move the axles back even a hair that'll aid in taming the issue.  A wedged plate that angles the whole gear back even further would not be amiss either if the wheel axles are well forward of the CG lcoation.

When the model is lifted to level at the tail you want the angle from the true 3D location of the CG to the axles to be about 30 degrees.  To find roughly the true CG location you can balance the model from the upper wing tips and find the vertical line and then hang the model from the wheels and where the two plumb lines cross is the true 3D location of your CG.  If this second hanging from the wheels line is a lot more angled forward then 30 degrees then figuring out a way to angle the gear back to reduce this angle would aid in reducing the ground squirreliness.