Yes, a button to lock / unlock a path, like in Master of Magic for Mana/Research/Skill if I remember well, would be great.
And the + / - should add / substract points 1 by 1, it's always frustrating to spend time trying to adjust precisely research, and not succeeding at it.
Something more, when choosing a school to display the list of spells, the spells are sorted by levels. Near of the level, it would be nice to have the research points needed to reach it.
Ex :
Alteration 1 : OK.
...
...
... List of spells
...
...
Alteration 2 : OK.
...
...
... List of spells
...
...
Alteration 3 : 43 remaining.
...
...
... List of spells
...
...
Alteration 4 : 203 remaining.
...
...
... List of spells
...
...
etc...
OK, it's actually possible to calculate it if needed, but it would be more comfortable to have it displayed.
