Firstly, it is a hybrid Jujutsu style, though it does not seem like it. It was developed by Antonio Pereira, a retired US Military Man from the Bronx, NY - I knew him too. They use classical jujutsu technique in a more modern format.
Daito Ryu, is one of the Major Branches of Classical Jujutsu from Japan. Their methods and curriculum are not very modified. Very traditionally Classical in every aspect.
One thing - atemi is profoundly present in both styles. Because you don't see it, does not mean it is not there.
Miyama Ryu was created by an individual who studied in judo, aikido and jujutsu, and then sprinkled in some boxing and other street fighting tactics as the result of a personal journey into what he believed was most effective. Daito Ryu will probably present you with a more traditional and perhaps not as varied menu of techniques, although it was also the result of one man's experience in jujutsu, sumo, sword and personal views/preferences. The founder of Daito Ryu had the founder of aikido as one of his students. I was fortunate enough to have met and taken some seminars with John Denora and his students. His technique, focus and character were all top notch. The guy was one of those folks who you meet on the mat and you just know that they are in a rare class. Of course, his background is as varied as the folks I've mentioned above, holding very high rank in many arts.
Go and visit each class. Do some research on the instructor at each and see how the class is run. If you like what you find out, sign up. Both of these have the potential to be great arts for you.
If your choice is between the two styles then you need to find the better teacher. A style does not guarantee you good training or that your teacher will teach you all that is contained in that style. So always go with the better teacher.
I am not familiar with Miyama Ryu but I am familiar with Daito Ryu. I train in Yamate Ryu which is an offshoot of Daito ryu and the closest Aiki school for me to train in. We train strikes because how can you learn to defend against strikes if noone in your school knows how to hit. Do they hire Karateka for you to practice on? So don't dismiss striking as being unnecessary. If you know the mechanics of something, like a strike, you will know so much better how to defeat it.
all forms of martial arts are affective but it depends on you. what you put into it, you get out of it. i have fought in many karate tournaments and have trophies from many different styles. does it mean that my style is better? it only means that i was a better fighter than they were. i have been a black belt for many years. good luck in your pursuit
Both styles appear effective and self defense oriented, without an excessive amount of attention to Atemi Waza, which is what I'm looking for.
What are the functional differences between the styles? What would you see in one that you wouldn't necessarily see in the other?