Hi Ellen! I know it can be frustrating, but if it makes you feel any better, I can
definitely see that you're improving.
I agree with Sherry, good paper definitely helps... the Rhodia pads are awesome. You might be putting
too much pressure on yourself... maybe take a day or two off now and then, don't look at your stuff, then come back to it with fresh eyes. Sketching letterforms with a pencil first might help you get into the flow a little easier, too. Play around with the consistency of your ink/gouache by adding more or less gum arabic, distilled water, etc. Try taking some big deep breaths before you write, consciously releasing all the tension in your shoulders/neck/arms/hands when you exhale.
I dunno, just some ideas that may or may not work... everybody's different. But definitely just have fun with it!