an EOL derivation for a takeoff chart
Where do you get the EOL term from ? Superseded term replaced by STODA a long time ago.
What one uses as entry data will depend on the presentation for the particular Type.
Wind is disregarded in taf calculations (forecast conditions), in AFT slope is disregarded too
Disregarding headwind for planning is useful as a wind change might leave you embarrassed .. but it has to be accounted when you get to the cockpit. Slope is required to be considered and there is no reason not to - it isn't going to change during flight planning.
exceedance of BRW/taxi out weight
Limitation the same as any other. If the calcs indicate you are going to exceed it, reduce the weight .. either fuel or payload.
given we cant reduce a given trip fuel load
You might have some pad in the fuel reserves .. it may be feasible to cut back towards minimum reserves.
the only option is a payload reduction
If that's all you have to play with .. throw off some freight or pax bags for the next flight