If I have understood your main queries correctly...
1. The terms 'progressive' and 'continuous' are entirely synonymous: some grammarians prefer one, and some the other.
2. Tense-forms such as 'I am eating' - which contain a present participle (eating) - are consequently labelled either 'present continuous' or 'present progressive'.
3. The opposite of 'progressive/continuous' is 'simple'.
4. English actually does have both perfective and imperfective aspects. Perfective verb phrases are those formed with a past participle (have done, had been doing, etc. ) All others, e.g. present simple or past progressive, can be technically classified as imperfective, but (most probably to avoid confusion with the use of the same word in French and German grammar to denote specifically certain past tense-forms, aimais, wohnte, etc.) the term has not acquired popular use in English. However the full tense-aspect label of the verb phrase I am eating, for example, would be PRESENT IMPERFECT PROGRESSIVE.
I trust I have covered the main points!