PhD without MA

Whether you can go straight from undergrad (or PGCE) to PhD depends very much on the PhD project, your background for it, the supervisor's perspective on the matter, and even departmental/university policies...it's in theory possible although generally more common in STEM subjects to go straight from undergrad to PhD. You can do PhDs in various aspects of education, and there are several departments quite involved in educational research (e.g. UCL and Cambridge).

If you want to go on to do a PhD you will need to submit, as part of your application, a project proposal (or a statement of purpose while applying to a specific advertised and funded project). It's not something you can just ask people on the internet for "ideas" on, as it's something you'll be working on for 3+ years and will inevitably be dependent on the research focuses and supervisor availability in the universities you apply to. That is something you will need to figure out for yourself (and is the first step in the independent research process that forms a PhD anyway).

Philosophy is notoriously competitive simply because there are lots of smart philosophy students with no direct career routes other than philosophy lecturer.

I'm aware that some universities stipulate a masters as a minimum requirement. For those that don't, you are likely to get out competed by other candidates with masters unless you have an exceptional academic record and a strong research proposal.

I went straight from a-level to BA (hons) then straight to PGCE so no long-term experience other than placements.

and as for the 3rd question I was only asking for ideas to spark my thinking not a question to focus on. I am aware i am required to write a proposal which i am more than happy to do, i love conducting research i just wanted some advice from anyone who has completed a phd in a similar topic as to what they focused on.

I don't think work experience in an educational sector is necessarily going to be relevant to go onto educational research, unless it's on some specific aspect of methods of pedagogy (and even then it may suffice to observe teachers and gather data once you're on the PhD).

For the latter point, honestly you would be better off browsing the research pages of various education departments at unis in the UK to see what actual researchers are doing research on - many if not most of the people on TSR will only be undergrads or school students, so their responses may not really be that indicative of what is of interest to academic communities.

A PhD in Education, or a PhD in Philosophy? Maybe blend the two into in the Philosophy of Education?

Just doing it at your current uni cos it is easier or has slacker requirements is not a great idea (not saying you are doing this, but your posts raise that possibility). As a bare minimum before even considering an application, you ought to have a research question already in mind and, consequently, potential supervisors. To compete for a place, funding etc you will need an exceptional undergraduate record, and as Trotsky says, you will still be disadvantaged next to those who have exceptional undergraduate AND exceptional Masters records.

Your best bet is to ask potential supervisors what sorts of stuff they'd be interested in doing and how they recommend approaching this given that you have no MA but do have a PGCE. The other option would be to see if you can transfer PGCE credits to an MSc in education or educational practice (etc), do that course, then apply from that position.