Oil filter should be the best one always, actually no compromise on following;
Its type; Semi synth / Synthetic (if Minerals only premium grade otherwise not), It's Stability (shearing stability) and Cleanliness properties (Sludge removal). Viscosity matters after all this. 20w50 is ok if certain OEM has specifically mentioned it otherwise too thick of an oil. 10w40 gives a little better free pace to engine while 5w30 oils are for economy and better startup and go in cold mornings.
No.2 Oil Filter
It should be genuine and as good an option available for your vehicle as possible. For Cuore I suggest, Denso Made in Thailand (Toyota genuine Part) is the best oil filter available here. Available for Rs.450 a piece from Lahore Filter house shop.
No.3 Air filter
Air filter should be of near OEM quality if not OEM. I suggest to get at least a Le-Ppon air filter (dark grey color) Rs. 400 from Lahore filter shop it is available. But the real thing is; with wash at every weekend or every alternate weekend, I get my filter out and cleaned thoroughly by air pressure. So it is always clean, never dirty. I change filter after 1.5 to 2 months max as Le-PPon type filters are not good enough to work past 10,000 km or 2 months.
I used Shell Oils HX7 5w30 (semi-synth) in winters and Helix Ultra 5w40 (full synth) in summers. I believe in backwards compatibility of better brand of oils especially those which clearly mention A3/B3/B4 certifications and VW, MB, Porsche type of strict approvals. These oils have quality substitutes of Zinc/Phosphorous used in optimal lubrication of older engines.
However, I was having slight (very subtle) oil reduction issue when driving aggressively or noticeable at rate of 500ml per 4000Km.
What I like in Liqui Moly brand of exotic oils is that they have specialized formulations to nearly each and every type and condition of engine. LM even has different specialized oils for the group of Hondas, Toyotas, Mazdas etc. So here the oil I chose was (Super Leichtlauf 10w40 Semi synthetic. Rs.3000/- from Filter house Lahore) having High additives of Seal Conditioners (seal conditioners are present in Better/premium names of Full & Semi Synthetic oils) but this oil has specialized application on Older engines with higher mileage like mine (200k + Kms).
It has helped me so far that my oil reducing trait has slowed down to an extent it seems almost non-existent. My oil is at Full mark at dip stick after 1000km.