1/ Doubts about materialism - I thought that was all women and not just filipina, so to me it's no big deal.
2/ Texts from other lovers - I d consider them 'sleepers' to be reactivated in the event of your relationship going down the pan. Like an insurance policy. Don't like it ? Delete all the numbers from the phone and text them back a bunch of requests for money for support for the baby and see the texts miracously stop but if they don't you are alerted to a non sleeper relationship, to take action against.
3/ She wants you to buy land and then a build a house on it. - Show me a filipina who doesn't ?
4/ Maintaining many online personas - install keylogging software - you ll either discover that they are harmless 'sleepers' or that some are 'daywalkers', i.e. active relationships that are subsisting. Either it ll be good or terrible. But what will be good is you found out earlier rather than later.
For the record, I think from what you say, that you are correct to have your doubts. Your doubts are a subconscious alert to you to avoid danger I think.