1. Yes, you can supply the values=(-0.2 to 0.3 by 0.05) on the x axis to get the tick values you want. This will also set the axis data min and max to the extreme values you provide. However, some values may not display if there is not enough space on the axis, and they collide. To see the values you provide either make the width of graph bigger, reduce the font size or set appropriate FitPolicy. 2. The legends are in the order in which the group values are encountered in the data. First group value in data is first in legend. To force the legend to always be in the order you want, you can add dummy values at the top of the data.with the appropriate group values but missing x or y axis value. 3. Axis tick values start drawing based on THRESHOLD. To always get an outer tick mark, set axis THRESHOLDMIN and MAX to 1. Refer doc for explanation of THRESHOLD. In your case you are already using Threshold min and max. Since you are adding scatter for data labels, the data label is setting offsets. you can set offsetmin and max = 0. Note, bubble at upper end of x axis is clipped.
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