Maybe I am being daft but can you replace all the characters from where the cursor is to the end of line by one command? Then use . to do the same replace on the next line and so on.
Adding to sr_'s answer:
If your cursor starts at the same position on each line, you might be interested in the Visual Block feature.
Type the following in order, with your cursor in the initial position:
- Ctrl+v: Enter visual block mode.
- $: go to the end of the line.
- [X]j: replace X with the number of lines you want to go down.
This should create a rectangular selection going from your cursor on the first line to the end of the line [X] lines below.
You can then replace your whole selection:
- c: delete selction and go in insert mode.
- insert new text
- Esc: Exit insert mode; Vim will automatically repeat the step on each line selected.
I use visual block whenever I can, I thought I'd share