PhD-SLP

I am currently a second year M.S. in SLP student, and I am enjoying my thesis research experience so much that I am very seriously considering pursuing a PhD after I get my C's and practice for a year or so. I am aware that research experiences and interests are often weighted more heavily than GPA/GRE for admission to PhD programs. Questions: (1) I did not participate in any research whatsoever as an undergrad, and I am trying to gauge whether or not completing a masters thesis (a year-long process at my school, I'll be collecting/analyzing the data myself and reporting) and trying my best to join other research projects during my final semester and a half (I've already spoken with several professors about this, I'm waiting on word back) will be enough to make me competitive (research-wise) when applying to PhD programs. Worst case scenario: the only research experience on my resume is my masters thesis. Best case scenario: I have my thesis and 1-2 additional large scale research experiences on my resume. Do most people who apply have significantly more research experience than this? (2) Do most applicants apply to PhD programs after graduating with their bachelors? Or is it more common to apply after completing the clinical masters degree? Basically, would already having my masters and C's give me an advantage, or is it very common for applicants to have a masters/their C's already? If it helps contextualize my questions, I am specifically curious about programs in Massachusetts (BU's PhD in Speech-Language and Hearing Sciences, MGH's PhD in Rehabilitation Sciences, Harvard's PhD in Speech-Hearing Bioscience, UMass Amherst's PhD in Communication Disorders). For what it's worth, I do have research interests (that I can easily speak to in application essays) that align with at least one professor/PI at each of the institutions I've listed. Thanks so much in advance to anybody who's able to give me any advice!