CS-Hover,
The reason you haven’t had too many replies is that you have asked a question that needs to be qualified to be answered. However, I will add some views to give the thread a kick.
Because of your second post (and because it makes it more interesting), I will take the case of a twin that is operating in Performance Class 1 using Category A procedures.
Let me take the case you started off with - a runway with unlimited length for take-off and landing: most modern helicopters can take-off and land using the Clear Area (runway) Cat A procedure at the maximum certificated mass at Sea Level and in ISA conditions - well within limits; the cruise will not be limited at 2000ft (most helicopters would not see a decrease of cruise speed under those circumstances).
Now let’s make it more interesting by raising the temperature until the helicopter is taking off at MUAM for the Clear Area procedure. Because there are no rejected take-off or obstacle issues (your conditions), the first segment (100ft/min at Vtoss at 200ft) and acceleration segment (power to accelerate from Vtoss to Vy) pose no problems and the likely limitation will be the second segment climb performance (150ft/min at Vy at 1000ft above the take-off surface).
Having established that we can climb at 150ft/min at Vy at 1000ft, experience (many calculations) tells us that the cruise limit (50ft/min at Vy at cruise altitude) occurs at approximately 1000ft above the second segment climb limit. The second segment climb is planned at the 30 minute power (which in practical terms is usually the same as the MCP) - which results in the take-off and 2000ft cruise limits being reached at the same take-off/landing mass.
If we now change the take-off or landing conditions - i.e. we shorten the runway, or add obstacles, the take-off or landing mass will be limited but the cruise conditions (at 2000ft) will not.
The most limiting take-off mass will occur when the helicopter has to reject onto a helipad, or has to clear obstacles in the take-off distance required (TODRH) or in the take-off flight path (obstacles in the take-off flight path will require an increase in the climb gradient - i.e. less mass). The take-off mass will be highest for the Clear Area procedure, less for the “Restricted/Confined Area - Short Field” procedures, and least for the Helipad. As the take-off mass decreases so more power is available for the cruise (at the reduced cruise mass).
Jim