How’s it supposed to be

hey all

Continuing on getting my 69 dart reliable
(225/904/3.23’s)
Was really hesitating when I first got it and pissing fuel so since I got her I:
Rebuilt carb
New vac lines
Checked timing
Adjusted valves
Pertronix
Plugs
Cap
Wires
Coil

Car really woke up. Almost like a modern 4 cylinder. So, here’s my question....is it normal?
My quick barely rolling test in my 69 four door brought a rough 0-60 time of 20 seconds
Butt feel is:
0-10 great
10-35 slow
35 and up great.
Is that normal?
Uphill has no balls. Like second gear (904) and slow putt putt up. This is up a steep hill
And does the 904 seem like it shift 1-2-3 quickly? Like it doesn’t hold the gears very long?