As for hiring foreign players, I think it is better for Indonesian football clubs to hire the best players from neighbouring mid-ranked Asian countries like Singapore or Malaysia or Thailand rather than low-tier South American or African players of unproven qualities. Asian players will arguably set up lower transfer fee, and in the same time this action will support the development of regional football teams. Another good possibility is to hire potential young players from top-ranked Asian countries, like those in East Asia or Middle East. I think borrowing Zeng Cheng was a good move by Persebaya. It would be even better if they could hire him permanently as he was a good player in his age and also a potential national team goalkeeper.
In fact this is my approach when playing PSM Makassar in Football Manager. I bought good young players from Bahrain and South Korea, one veteran goalkeeper from Costa Rica (I’ve been widely known for not buying old players, but I’ve got excuse: not many choices available for goalkeeper position), one Uruguayan player who had been playing in Indonesia for a couple of years (Ronald Fagundez) and one national star from Uzbekistan. Well, apart from them we also had Syamsul Chaeruddin, Ponaryo Astaman, Ilham Jayakesuma, Zainal Arifin etc who had been regularly featured in Indonesian national team. We managed to be finalist of Club World Championship, beating River Plate (or Boca Juniors, I forget) 4-0 on the way and only losing by penalty against the godlike Barcelona. :-“