The poet William Wordsworth is a good choice for English assignments and essays on traditional English poetry because this poet displays all the characteristics of the genre of English Romantic poetry. The Prelude would be a good option - it gives sufficient subject matter, beautiful quintessentially English landscape images, Romantic themes such as the beauty and power of Nature and concepts of duty and tradition. Also, Wordsworth has an interesting biography and is very well known for famous poetry such as his memorable poem about daffodils. Themes of bereavement, old age and life after death are other possibilities.
You might also consider Christopher Marlowe's "The Passionate Shepherd to his Love." This well-known poem was written during the Elizabethan era and is concerned with romantic love. The poem is dense in figurative language, has a defined rhythm, and offers much content to explore. In addition, the poem sparked several responses from other poets, most notably Sir Walter Raleigh's "The Nymph's Reply to the Shepherd" which you could also discuss in the essay.
If you're looking for suggestions, I can recommend one for you.
Matthew Arnold's "Dover Beach" is famous and much criticism or analysis of the poem is available. It is also not particularly difficult, as long as you know a little history. The poem is somewhat of a "poster boy," metaphorically speaking, for the Victorian predicament. With the advancement of science, particularly Darwin's theory of evolution, faith in a divine being became difficult for thinkers. This poem relates to that issue.
The poem is a dramatic monologue, featuring a speaker addressing a silent listener. It also contains a classical allusion or two. In other words, there are plenty of details in the poem to analyze.
I think that some level of specificity will be needed because this is a fairly huge topic. To generate 3000 words on any poem is something that can be done. This makes the need for specificity as a critical one. For example, which time period in English Literature are you examining? What literary movement are you planning to study? Do you have a specific poet in mind? In my mind, it is critical to assess these question and narrow it down a bit. Certainly, enotes editors won't be able to write it for you, but providing some specificity to the topic area might allow you to receive some secondary insight that could help make your writing stronger.
Unless you make a definite choice, it will be difficult to provide the lead. Yet you can try on the model structure as given below:
a) Some brief bio-critical observations on the poet, his/her period, and salient features of his/her poetic credo;
b) Date and particular occasion of Composition;
c) A crtical summary of the text of the poem;
d) Some special comments on its theme(s), genre, form/structure, metre, imagery, symbolism, message(if any);
e) Acknowledgement of major critical responses to the poem;
f) Your personal responses including reference to a parallel text, permanent value, blemishes(if any).