Some of these additional interventions and modalities include:

biofeedback
dyadic resourcing (used with EMDR)
emotionally focused therapy
emotional freedom technique (EFT) or tapping
equine-assisted therapy
expressive arts therapy
internal family systems therapy
dialectical behavior therapy (DBT)
family systems therapy
group therapy
neurofeedback
psychodynamic therapy
sensorimotor psychotherapy
somatic experiencing
yoga, specifically trauma-sensitive yoga

Arguments against diagnosis
Though acceptance of the idea of complex PTSD has increased with mental health professionals, the fundamental research required for the proper validation of a new disorder is insufficient as of 2013. The disorder was proposed under the name DES-NOS (Disorder of Extreme Stress Not Otherwise Specified) for inclusion in the DSM-IV but was rejected by members of the Diagnostic and Statistical Manual of Mental Disorders (DSM) committee of the American Psychiatric Association for lack of sufficient diagnostic validity research. Chief among the stated limitations was a study which showed that 95% of individuals who could be diagnosed with the proposed DES-NOS were also diagnosable with PTSD, raising questions about the added usefulness of an additional disorder.Following the failure of DES-NOS to gain formal recognition in the DSM-IV, the concept was re-packaged for children and adolescents and given a new name, developmental trauma disorder. Supporters of DTD appealed to the developers of the DSM-5 to recognize DTD as a new disorder. Just as the developers of DSM-IV refused to included DES-NOS, the developers of DSM-5 refused to include DTD due to a perceived lack of sufficient research.
Complex post trauma stress disorder is a long term mental health condition which is often difficult and relatively expensive to treat and often requires several years of psychotherapy, modes of intervention and treatment by highly skilled, mental health professionals who specialize in trauma informed modalities designed to process and integrate childhood trauma memories for the purposes of mitigating symptoms and improving the survivors quality of life. Delaying therapy for people with complex PTSD, whether intentionally or not, can exacerbate the condition. Recommended treatment modalities and interventions
There is no one treatment which has been designed specifically for use with the adult complex PTSD population (with the exception of component based psychotherapy ) there are many therapeutic interventions used by mental health professionals to treat PTSD. As of February 2017, the American Psychological Association PTSD Guideline Development Panel (GDP) strongly recommends the following for the treatment of PTSD:
Cognitive behavioral therapy (CBT) and trauma focused CBT
Cognitive processing therapy (CPT)
Cognitive therapy (CT)
Prolonged exposure therapy (PE)The American Psychological Association also conditionally recommends
Brief eclectic psychotherapy (BEP)
Eye movement desensitization and reprocessing (EMDR) 
Narrative exposure therapy (NET)While these treatments have been recommended, there is still on-going debate regarding the best and most efficacious treatment for complex PTSD. Many commonly used treatments are considered complementary or alternative since there still is a lack of research to classify these approaches as evidenced based.