What kinds of medications is the hospital staff going to be giving that is going to wear off during transport for your BLS patients?
Treat the patient as a BLS provider and made a decision on what is going to be best for the patient (contact an ALS unit, divert to the closest hospital, or continue transport to the original destination).
If you're BLS and you need to take a trauma patient 90 miles to a trauma center, and the patient is likely to need ALS intervention during transport, you need to bring that up. If you have a seizing patient, you don't have to do much... you keep the patient safe, apply oxygen as necessary, provide ventilatory support PRN, and transport to the closest, most appropriate facility. What would you do with that same patient in the 911 arena? Most of the time you don't have to do much beyond that. You need to think about your options... and that may include calling for ALS.
What would you normally do if you had a patient in your ambulance and they start seizing?
Sometimes, you have to stop worrying about being sued. You've already mentioned that you've been sued multiple times in multiple threads. To a point, we already practice defensive medicine but if you have that thought constantly hanging in the back of your mind about getting sued, you won't be able to perform properly. Anecdotally, I work with an ER doc who has been sued and overorders a lot of unneeded tests and labs (he has built quite the reputation of ordering everything under the sun) and just practices medicine unlike any other doc presumably because he's scared of getting sued again. Now whether you are doing something wrong that you are getting sued as a BLS provider three times is a different discussion.
You probably need to have someone sit down with you and truly school you about things like "abandonment" and "negligence" and "competence." You do not seem to understand these things as it pertains to EMS, and medicine in general. What you also need to understand is that sometimes a patient that's very sick only truly needs BLS for transport but also needs the surgeon waiting for them on the other end. As I've said earlier, if you're not comfortable taking a patient because you believe and can clearly articulate why a patient requires care beyond your ability, it's incumbent upon YOU to speak up and say so. Worst case scenario is the sending facility must send someone that's qualified to provide the level of care necessary. However, the onus is primarily on the sending facility to determine the appropriate level of care necessary during transport. They may not exactly know your limitations, but they know that if a patient doesn't need a monitor or doesn't need anything other than a basic IV fluid running during transport, BLS is appropriate. ALS can do many things... but the choice of CCT-RN is necessary if the patient requires ICU level care during transport. They know those basics... and if YOU know those differences, YOU can help them choose the most appropriate transport resource and it may NOT be your company.
That's going to be system dependent. There are a number of systems where paramedics will hand over care to an AEMT or EMT. I believe Los Angeles does this (fire medics and private BLS company responds to all 911 calls, the medic assess the patient and then deems the patient needs ALS or BLS).