Let me just tell you this: Prominience and Fireball are not that much. I’ve both classes and tested both skills and they are not that great, specially as the games goes on.
Psychic Pressure is what has been stated: you need either wiz2 for Surespell for it to work or Kino3 for attribute Focus. Telekinesis is a fun skill but it’s for PvP. Heavy Gravity is an amazing skill, you should get it.
Summon Familiar: you go for level 10+ or don’t. No in between. Summon Servent is a must. It is really good
Just wait for all the buffs before you go.
I too was a pyromanic and like fire-related spells. But playing this game for 2 years has made me disappointed the way it is played off. By no means I wan’t to tell you what you must do and not to do. You can try and make it all work. The big problem is how hard will it be to pull that off. I’ve been there. This is all an advice from a person who wanted a custom build by myself just to take longer and harder to progress through the game.
I’ve kind of re-made those skills tree a bit. If you want to check it and compare.
Summon Minion: http://www.tosbase.com/tools/skill-simulator/build/d39gur8wlk/
There is more room for skill points for your taste. There is also no need to invest points in Hold or Attack Ground. Altough Attack Ground can be of use for strategically, speacially for solo. Both Necro and Summo have "Summon: Cancel/Attack and Release automatic invested.
Aoe Dps:http://www.tosbase.com/tools/skill-simulator/build/d39gur8wlk/
Howerver, feel free to disgard all of this. But I enforce you to read the doc @MrFioz has sent. It is really good and begginer friendly.