Perhaps you'll improve your workflow if don't fear to ... jump :)
Example:
This is where cursor initially is: _.
[Some other stuff you want to keep/skip ...]
I want to delete these lines.
I want to delete these lines.
I want to delete these lines.
I want to delete these lines.
I want to delete these lines.
Your actions (normal mode, cursor is on _
): /I want
Enter
5dd
Ctrl-o
. That's it.
Of course, romainlromainl answer is the best if all you want to delete whole lines, and you can count their offset easily (using relative linenumbers for example). The above is a more generic way to "act": go there, using something that counts as a jump: this means you can always jump back, after you modify the text.
For example, if you use absolute line numbers, you can replace the /I want
Enter
with something like 78gg
or 78G
to jump directly at that line number.