it seems that lavals and flamvells work well while they are in the graves. to put then as soon as possible in the grave u should use lightsworns and card trooper. if u dont wanna reckless mill ur monsters u can make an deck which abuses ''laval miller'' (lightsworns are faster). another option is running Draw/Mill cards like ''hand destruction'', ''card destruction'' and '' dark world dealings'' if u dislike random milling (be aware that in a Draw/Mill engine u will lose hand advantage).
cards like rekindling are used for big plays or even to have game. to be sure u succeed in doing that u should run ''giant trunade'' and ''trap stuns'' (prefer royal decree but u also uses other traps). as own preference i used trap stun to replace cold wave.
to be sure u dont mill the wrong monsters IF u noticed u do, add in ''pot of avarice'' and ''monster reincarnation''
also that even if FIRE monsters has the ability to burn, flamvells and lavals are an aggro type of deck. which means that burning is a nice addition but it focuses more on summoning beatsticks and overpowering of the opponents monster.
this is a quick build i put together ( UNTESTED ). i took some good lightsworns, lavals, and flamvells and put them together.
3 LS ryko
2 LS lyla
3 FL firedog
3 FL magival
2 Lav burner
3 Lav warrior
2 Lav forest spirit
2 Lav miller
1 soaring eagle above the searing land
2 card trooper
1 necro gardna
1 gorz / trago / b-fader ( w/e u prefer using )
2 rekindling
2 monster reincarnation
1 monster reborn
1 giant trunade
1 foolish burial
1 charge of the light brigade
1 solar recharge
1 solemn judg
1 mirror force
1 torrential
1 trap stun
2 royal decree
i hope it helps and if it doesnt, u should join my ham : LifeStreamDragon // 123
and we will work on it like in the good old times xD