Starting from level 11, the level bonuses are the most important part of a non-spell user development, so I don't think removing them would be a good idea. Just consider this chart, assuming a two-ranks development per level:
- From level 1 to 5, you develop ranks 1 to 10, therefore each rank grants a +5, for a total of +10 per level. Comparatively, the level bonus is +3 or 1/3 level,
- From level 6 to 10, you develop ranks 11 to 20, therefore each rank grants a +2, for a total of +4 per level. Comparatively, the level bonus is +3 or 75% of a level,
- From level 11 to 15, you develop ranks 21 to 30, therefore each rank grants a +1, for a total of +2 per level. Comparatively, the level bonus is +3 or 1.5 levels,
- From level 16 to 20, you develop ranks 31 to 40, therefore each rank grants a +0.5, for a total of +1 per level. Comparatively, the level bonus is +3 or 3 levels.
Comparatively, without his level bonus (not taken the statistic bonus into account), a level 20 has 40 ranks, for a total bonus of +85. With a level bonus, a level 10 has 20 ranks, for a total bonus of +70+30=+100!
Save mayhap for RRs purpose, there's little reason to play characters above level 10 if you remove the level bonuses.