Layovers:
LHR / MAN / LGW / CDG / MXP** / BKK / SIN / CEB / DAC / CMB** / CMN / CGK / MNL / PEK / JNB-CPT / KIX / ICN-PVG /
**Reverting back more commonly to the A300-622R as the primary aircraft used.
The A332 is also used regionally on routes to: DXB / KWI / BAH / JED / CAI^^ / AMM^^ / BEY^^ / DAM^^ / PEW / ISB / RUH^^
^^ as a fill-in mainly. These routes are primarily operated on A300-622R / A320 / A321 equipment.
Cannot comment on the rationale or protocol employed by the crewing department in terms of how many layovers one can expect in a roster per month, compared with regional turnaround flights.
I know of some pilots who are perpetually operating Far East Long Haul layovers, and who rarely go to Europe, for example. Some of the pilots here may be able to explain a bit more about the second part of your question.
Cheers.