It's a media frenzy with few facts and lots of conjecture

To date the Bangkok Bomber has made a clean getaway: Via  Lumpini park  That is a fact. 

Almost everything else you hear is conjecture.  Many headlines read "bomber identified," it's a very misleading statement.  No name has been put to the face.  No nationality has been identified.  All they seem to have is a very grainy picture.

Thai red-shirts were the first to draw the suspicion of investigators. That suspicion is doubtful. 
There are a few things all Thais agree on. Respect for religion and national heritage his high on that list.

"It's the doings of former dictator Shinawatra, a US puppet" according to one propagandist.

He's not Thai, they say he's a foreigner, he spoke a foreign language. His phone call may have been part of the deception.  No phone call would need to be made indicating 'mission accomplished.'  They'd get that from the media, social network included.  A pickup point would have been prearranged.

Those two guys providing coverage while the device was planted were identified as "suspects" instead of persons of interest.  As it turns out they were innocent bystanders who shrieked in dismay when the explosion occurred.

Media reports indicate the bomber has not left the country.  I consider that another opinion.  This country's borders are very porous.  How can one be sure.

There is speculation that the bombing was to hurt Thai tourism and subsequently the economy. Probably right.

Capture of the culprits as quickly as possible will aid in restoring confidence in Thai tourism, but then that's also just as opinion