Hi all !
Just my 2 cents if it is of any help...
Usually, I use Frescobaldi midi input if I have some notes to replace. For example, I'm frequently typesetting SATB hymns, for which the rythm is often the same between voices.
Frescobaldi midi input is very helpful for me in this case.
Some may use it by entering pitches on midi keyboard with one hand and durations on numpad with other hand but I'm not used to it.
To enter a (simple) complete voice with duration, I use Rumor in a terminal (connected to midi input and synth using Jack). If I remember correctly I had to build Rumor from source when I installed it couple of years ago.
Cheers !
Yann