There are various types of incarnations or expansions of the Supreme Personality of Godhead. The expansions of His personal self, or viṣṇu-tattva, are called svāṁśa expansions, whereas the living entities, who are not viṣṇu-tattva but jīva-tattva, are called vibhinnāṁśa, separated expansions. Although Prajāpati Dakṣa is not on the same level as Lord Brahmā and Lord Śiva, he is compared to them because he engages in the service of the Lord. In the service of the Personality of Godhead, it is not that Lord Brahmā is considered very great while an ordinary human being trying to preach the glories of the Lord is considered very low. There are no such distinctions. Regardless of whether materially high or materially low, anyone engaged in the service of the Lord is spiritually very dear to Him. In this regard, Śrīla Madhvācārya gives this quotation from the Tantra-nirṇaya:
viśeṣa-vyakti-pātratvād
brahmādyās tu vibhūtayaḥ
tad-antaryāmiṇaś caiva
matsyādyā vibhavāḥ smṛtāḥ
From Lord Brahmā down, all the living entities engaged in the service of the Lord are extraordinary and are called vibhūti. As the Lord says in Bhagavad-gītā (10.41):
yad yad vibhūtimat sattvaṁ
śrīmad ūrjitam eva vā
tat tad evāvagaccha tvaṁ
mama tejo-'ṁśa-sambhavam
"Know that all beautiful, glorious and mighty creations spring from but a spark of My splendor." A living entity especially empowered to act on behalf of the Lord is called vibhūti, whereas the viṣṇu-tattva incarnations of the Lord, such as the Matsya avatāra (keśava dhṛta-mīna-śarīra jaya jagad-īśa hare), are called vibhava.
(Srimad Bhagavatam-----6:4:45-----purport).

Although these four great sages were older than Brahmā's other sons like Marīci, they appeared like small naked children only five or six years old. When Jaya and Vijaya saw them trying to enter Vaikuṇṭhaloka, these two gatekeepers, thinking them ordinary children, forbade them to enter.
In this regard, Śrīla Madhvācārya says in his Tantra-sāra:
dvāḥ-sthāv ity anenādhikāra-sthatvam uktam
adhikāra-sthitāś caiva
vimuktāś ca dvidhā janāḥ
viṣṇu-loka-sthitās teṣāṁ
vara-śāpādi-yoginaḥ
adhikāra-sthitāṁ muktiṁ
niyataṁ prāpnuvanti ca
vimukty-anantaraṁ teṣāṁ
vara-śāpādayo nanu
dehendriyāsu-yuktaś ca
pūrvaṁ paścān na tair yutāḥ
apy abhimānibhis teṣāṁ
devaiḥ svātmottamair yutāḥ
The purport is that the personal associates of Lord Viṣṇu in Vaikuṇṭhaloka are always liberated souls. Even if sometimes cursed or blessed, they are always liberated and never contaminated by the material modes of nature. Before their liberation to Vaikuṇṭhaloka they possessed material bodies, but once they come to Vaikuṇṭha they no longer have them. Therefore even if the associates of Lord Viṣṇu sometimes descend as if cursed, they are always liberated.
(Srimad Bhagavatam-----7:1:37-----translation and purport).

Those who aspire to be elevated to the heavenly planets by devotional service will also be frustrated, because this is not the result of devotional service. However, they are also given a chance to engage in devotional service and be purified. As stated in Śrīmad-Bhāgavatam (1.2.17):
śṛṇvatāṁ sva-kathāḥ kṛṣṇaḥ
puṇya-śravaṇa-kīrtanaḥ
hṛdy antaḥ-stho hy abhadrāṇi
vidhunoti suhṛt satām
"Śrī Kṛṣṇa, the Personality of Godhead, who is the Paramātmā [Supersoul] in everyone's heart and the benefactor of the truthful devotee, cleanses desire for material enjoyment from the heart of the devotee who relishes His messages, which are in themselves virtuous when properly heard and chanted."
Unless the dirt within the core of one's heart is cleansed away, one cannot become a pure devotee. Therefore the word su-durlabhaḥ ("very rarely found") is used in this verse. Not only among hundreds and thousands, but among millions of perfectly liberated souls, a pure devotee is hardly ever found. Therefore the words koṭiṣv api are used herein. Śrīla Madhvācārya gives the following quotations from the Tantra Bhāgavata:
nava-koṭyas tu devānām
ṛṣayaḥ sapta-koṭayaḥ
nārāyaṇāyanāḥ sarve
ye kecit tat-parāyaṇāḥ
"There are ninety million demigods and seventy million sages, who are all called nārāyaṇāyana, devotees of Lord Nārāyaṇa. Among them, only a few are called nārāyaṇa-parāyaṇa."
nārāyaṇāyanā devā
ṛṣy-ādyās tat-parāyaṇāḥ
brahmādyāḥ kecanaiva syuḥ
siddho yogya-sukhaṁ labhan
The difference between the siddhas and nārāyaṇa-parāyaṇas is that direct devotees are called nārāyaṇa-parāyaṇas whereas those who perform various types of mystic yoga are called siddhas.
(Srimad Bhagavatam-----6:14:5-----purport).

Those who are engaged in the service of the Lord are not meant to struggle for existence. The devotees who are fully engaged in spreading the Kṛṣṇa consciousness movement, more than ten thousand men and women all over the world, have no steady or permanent occupation, yet we actually see that they are maintained very opulently. The Lord says in Bhagavad-gītā (9.22):
ananyāś cintayanto māṁ
ye janāḥ paryupāsate
teṣāṁ nityābhiyuktānāṁ
yoga-kṣemaṁ vahāmy aham
"For those who worship Me with devotion, meditating on My transcendental form, I carry to them what they lack and preserve what they have." The devotees have no anxiety over what will happen next, where they will stay or what they will eat, for everything is maintained and supplied by the Supreme Personality of Godhead, who has promised, kaunteya pratijānīhi na me bhaktaḥ praṇaśyati: "O son of Kuntī, declare it boldly that My devotee never perishes." (Bg. 9.31) From all angles of vision, therefore, in all circumstances, if one fully surrenders unto the Supreme Personality of Godhead, there is no question of one's struggling for existence. In this connection, the commentary by Śrīpāda Madhvācārya, who quotes from the Tantra-bhāgavata, is very meaningful:
sac-chadba uttamaṁ brūyād
ānandantīti vai vadet
yetijñānaṁ samuddiṣṭaṁ
pūrṇānanda-dṛśis tataḥ
attṛtvāc ca tadā dānāt
satyāttya cocyate vibhuḥ
Explaining the words satyasya yonim, Śrīla Viśvanātha Cakravartī Ṭhākura says that Kṛṣṇa is the avatārī, the origin of all incarnations. All incarnations are the Absolute Truth, yet the Supreme Personality of Godhead Kṛṣṇa is the origin of all incarnations. Dīpārcir eva hi daśāntaram abhyupetya dīpāyate (Bs. 5.46). There may be many lamps, all equal in power, yet there is a first lamp, a second lamp, a third lamp and so on. Similarly, there are many incarnations, who are compared to lamps, but the first lamp, the original Personality of Godhead, is Kṛṣṇa. Govindam ādi-puruṣaṁ tam ahaṁ bhajāmi .
The demigods must offer worship in obedience to the Supreme Personality of Godhead, but one might argue that since the Supreme Godhead was within the womb of Devakī, He was also coming in a material body. Why then should He be worshiped? Why should one make a distinction between an ordinary living entity and the Supreme Personality of Godhead?
(Srimad Bhagavatam-----10:2:26-----purport).