At level 70 you should be playing eriki's psalm of power, not rizlonas.
70 ancient song from anguish is even better if you can get a rotting rune.
War March is staple if you've got other melees in group, if you're the only one play jonthans mightful caretaker.
If you're playing in old raid zones with 5min ooc timer make sure you're playing manasong.
If your tank is really getting owned and you need to sacrifice some dps for survivability swap war march for verses of victory (big ac boost but no DS/atk).
Coldcrow's Spry Sonata is the lvl 79 upgrade to Niv's Harmonic - another nice AC boost.
Psalm of veeshan gives some ds + resists + ac - usually the first song to be dumped from my twist when a caster joins.
Dirge of the Darkvine is a mini-vie type buff for the tank in group.
Storm Blade is only mediocre dps (18-20 per melee).
Performer's Explosive aria is great if you have fire nukers (rangers, wizards, mages).
Garradels Fatesong is great if you have cold nukers (rangers, wizards, beastlords, shamans?)
Arcane anthem stacks with the 2 above if you have a lot of caster types (kinda like mana flare but lower dmg).
If you have a lot of melees and everything you're fighting is snare/slowable consider using largo's assonant binding - has a massive AC debuff and will increase your groups DPS.
If you're fighting unsnareable stuff that needs to be ac debuffed (vt trash is a good example) you can use denons disruptive discord, just be warned its also an ae dot and will mess up mezzing.
Consider keeping HoS in your twist if you have casters in group and resistive mobs (anguish trash?).
Add ancient: chaos chant for really resistive stuff (ToB group named?) - usually not needed if you have a shm in group tho for malos.
So yea asking what 4 songs should I sing is a pretty open ended question without additional info
