yes, that is the param that sets the maximum bank angle the controller will demand. there are aerodynamic limitations to that however, and i‘m not really sure if turning down the roll P, adding weight and cranking up the roll limit simultaneously is a promising combination. at least you’ll likely want to keep up your airspeed with some safety margin when demanding a 60° bank angle on an airframe with a compareably high wing load.
on a sidenote, SITL (simulation) is a pretty awesome tool to get familiar with all the ardupilot options without having to put your airframe at risk.
As Basti wrote, be careful when you raise maximal bank angel and airplane weight as the stall speed increases.
In a level 60° banked turn the loadfactor is 2 G. The aircraft weight has doubled and the stallspeed increases in proportion with the root of the weight. So Stallspeed in a 60° turn is 1.42 times higher than in straight flight.
I am not going to make all the changes said above in one go, one at a time.
At the moment my Lim_Roll_CD is set at 45 degrees (I have to bottom out my roll stick for 6 sec to make turns) . I will try 48 degrees after I have flown with mechanical linkages are moved to the end of the control arm and horn. I may have to increase “P”, but we will see.
Once this is out of the way, only than I will add another gimbal control axis.
As far as flying manual mode, I will climb a hill near my house and test this plan as a slope soarer without power.
I need to read more about how to use Simulator in MP. SITL is out of my league.