Is it important to have a family member in Canada:
In general term the answer will be NO it is not important to have a family member in canada to claim protection. blood relative/close family member requirement is only for those who claim refugee protection at USA-CANADA land border. people who make refugee claims inside canada or come to canada by air do not need to have family members in canada.
Refugee claim at US-canada border: people who are in USA (e.g on visit visa. legally living, studying, illegally living etc ) can come on Canadian border and claim a refugee protection (assuming they do not have a visa (TRV) to come to canada). to claim a protection at Canadian border they must have a close relative (spouse, children, parents, brother, sister, uncle, nephew etc ) otherwise they cannot. the reason is as you are already in USA (a safe place) you must make your refugee claim at the first safe place BUT if you have close family you can choose to make your refugee claim at Canadian border to facilitate family reunion. where to make the claim: at Canadian border where they have a RPU (refugee processing unit).
Refugee claim at Canadian airports: any person entering into canada legally or illegally can claim protection/make a refugee claim at airports. for such claim there is NO requirement of close family relatives to be present in canada. where to make the claim: at the airport when you meet the first CBSA officer/immigration officer.
Refugee claim inside canada or once you are in canada: any one who had entered in canada on visit visa (trv), student visa. is already in canada etc, etc.... can make a refugee claim while he is here in canada and he DO NOT need any family member to be present in canada.where to make the claim: You can make a refugee claim in Canada at designated CIC offices which are in almost all major cities.
If you have a family member in canada does it makes the refugee/asylum case stronger:
NO it does not. refugee case is accepted or rejected only the basis/reasons of your claim. a refugee case is only strong if you are unwilling to return because of a well-founded fear of persecution based on race, religion, political opinion, nationality or member of particular social group.
IRB can no way grant you refugee status only for the reason that you have family members living here.