It should be up to par with the 201 when it comes to speed, at least with the belt motor setup. It's not particularly fast, but not unreasonably slow. How is the tension dial numbered? When test sewing and working with settings, it's the general routine; two layers of light to medium weight cotton (quilt/shirt weight), sew-it-all type thread weight (don't go for top stitch or very fine right away). Set top tension dial about half way between its' extreemes; then ajust bobbin tension.
Make sure top tension works by threading the machine; when pulling the top thread tension should gradually increase as you turn the dial up. Make sure the machine rease tension when presser bar lever is up, and grips thread when down.
This video will give you and idea about speed and stitch length.
Generally regarding stitch length issues; problems is usually connected to oiling and cleaning. If any part involved from stitch length adjuster to feed dogs is slow or frozen it will interfere with feed, speed an stitch length. It can be a case of tentative oiling for a while and moving whatever knows and levers this machine have. Whipe off motor belt and pulleys to remove any oil. Oil all pooints and wham it at full speed for a bit and see what happens.