Is this worthwile to make published a short scientific essay, 1 page or less, that criticise the current trends or suggest a new research line? in which type of journals?
You are describing a letter to the editor. Most journals will accept these. But perhaps keep new research lines confidential for yourself for the future!
Most scientific journals have a section inside the journal for "brief communication". You could locate this section and observe the requirements of the journal considering this type of writing.
As your intention is to criticize the current trends or suggest a new research lines, 'letters' would be the apt choice. Letters are regular features in weekly or fortnightly journals such as Nature, Science, and Current Science. Note that unlike short communication, however, only a few journals accept and publish letters from researchers.