Help: Mitsubishi Adventure Gas Major Service Time

My pal's Adventure (gas engine with A/T) is currently at 170,xxx kms and we are planning to do the 200,000km service already.

Here are the parts we intend to replace:
*Timing Belt (big and small)
*Water pump
*Oil, air, fuel filter
*Brake fluid
*Gear Oil
*ATF
*Tensioner bearings (there are apparently three of them due to the 4g63 having balance shafts)

Some photos:
***Two timing belts. One for the engine, and one for the balance shafts
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***Three tensioner bearings by Koyo and NTN
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***GMB Water Pump
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***Oil and fuel filter
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***Air filter
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My questions are:
1. Do the spark plugs need to be replaced also? What are good (and cost effective) spark plugs to use. The vehicle spends its life as a runabout in Pampanga.
2. Any other items that should be done while the engine is apart? Other items that can be done soon after? We are just trying to fly on a modest budget (need to buy a set of tires, too).

Thank you guys.