hello friend,haha your problem is so popular to people,to be honest,even though i am chinese,but i am not good at pinyin,i am lazy to study it when i am a child,so i rarely use them!
Pablo is spanish name?? you know i don't know spanish at all,so how can i compare your name with pinyin.let me try
in spanish it seems separate Pab and lo,but there are syllables, ba bu luo
yes,i think you are right. it would be better use Ba than pa
the tones of each syllable 124,i suppose like that,
i am not expert in Pinyin,i am sorry i didn't help you!