A fixed, manually adjustable chart scale (across all charts if possible), with: 1)no rescales when relaunching cTrader. (all the charts get streached)
2)no rescales when big moves happen.
3)no rescales when scrolling.
4)PLEASE NO RESCALES.
Please see my idea which incorporates yours with a few more benefits.
Go vote and make suggestions @ http://vote.spotware.com/forums/229166-ideas-and-suggestions-for-ctrader-and-calgo/suggestions/35928451-chart-scale-enhancements
you can create an indicator with two series, one for top and one for bottom and adjust them for a +/- percent of range.