Ticking
Just as a pointer, if the ticking is still there with the heavier weight oil but only after it has warmed up then the damage is already done. The wear once occurred, can not be reversed, if you file the corner off a lump of steel, it does not grow back. This is the case with the worn valve follower. The gap between the follower and the cam is not essentially critical, they can function for many many thousands of miles before they need major repair even when slightly worn. If the gap has worn by lets say 4 or 5 thousands of an inch, it will tick. The thicker oil will place a heavier film between the cam and the follower and quieten it down until the oil reaches its optimal temperature then the film thins out and the ticking will start again.
The weight of oil is also not so critical unless you are running a super car with masses of power.
Look at the way oils perform, they start cold and when cold they will be slightly thicker, but any oil producer will recommend you warm your engine before use. This is because all oils worm at an optimal temperature to give there best performance, so in theory the oil, regardless of weight will eventually reach the same viscosity as any other iol used in the engine. Eventually (at optimum temperature) all engine oils reach the same viscosity. This is why the ticking comes back when the engine is warm.
Your change frequency is good at 5K, if not already using it, try a full synthetic oil. What can happen is micro debris carried by the oil and filtered by the oil filter can find its way under the hydraulic valve lifters and cause one or more to stick . When the engine gets worm its tolerances get tighter and the micro debris can cause the lifter to stick and not react as quickly as it should.
I had this on my freelander, so I got full synthetic oil but flushed my engine by adding 1 pint of diesel to the oil before changing it, let the engine run to its correct temperature, then when cool enough to handle, I dropped the oil while still hot.
New filter and new synthetic oil. fired the motor up and let it reach temperature again before taking it for a spin. Presto, ticking gone.