Submitting directly to the consulate is similar to DIY project. Though the process looks may looks easy on the surface, in real life it may turn very sour.

Consider the following comparison: you need to construct a deck. There are plenty of the on-line advice, books, manuals, etc. There are plenty of the materials in the stores like Home Depot or Lowes. Do you have previous experience in construction of the deck? Will you venture to do it completely on your own? You may do it so. What the final product will look like? Will it be solid? Will it look attractive? Will it meet all the codes? There are so many questions after all the time and money spent!

Same is with the travel visas: you need to have extremely thourough knowledge of the requirements, procedures, processing timings. One mistake and you are back to square one. And with visas the timing is also a big issue. And do not forget that the embassies and the consulates are the representatives of the foreign government that are beyond Canadian jurisdiction, i.e. Canadian laws does not spread onto their activities.

Summing it all up: you would be much better if you have highly experienced professional organization like Visa Center to represent your interests before the consular offices.

More information on the topic may be found here: http://www.visacenter.ca/why.html