What you say is worth a lot.
I can appreciate Brahman as being the absolute (core, essential, and constituent) form and nature of Reality from which all all other realities materialise and on which they are dependent, and I know about Ishwara as the natural truth mechanism of our pragmatic existence. I have for a long time realised that there is a part of me which has a connection with Ishwara (the natural 'order' of our pragmatic world, or Vishnu the Preserver) through what I call the truth consciousness mechanism of Nature. In a post to the website Advaita Vision recently I called this connection a 'spirit' because scientists have not found a biological tissue or organ that can be called the atma. Is this spirit what you are call Paramatma? How did you realise the existence of Paramatama, please?
The spirit you are referring to is the ātmā, jīva or jivātmā. Which means - you, me, him, her...all of us.
Supreme Lord - Kṛṣṇa is the 'bigger than the biggest'. This aspect is realized as the all pervading infinite Brahman. This Brahman is the effulgence coming from the body of Supreme Lord.
Parmātmā on the other hand is the Supersoul. It represents the 'smaller than the smallest' aspect of Supreme Lord. The living entity (Jīva) is one ten-thousandth the tip of a hair in size; but the Lord is so inconceivably small that He enters into the heart of this particle. As the Supreme, He can enter the atom and into the heart of the smallest, and control him as the Supersoul.
The personal feature of Supreme Lord is Bhagavān. That is Kṛṣṇa.
Lord Bramhā prays in this way:
isvarah paramah krsnah
sac-cid-ananda-vigrahah
anadir adir govindah
sarva-karana-karanam
Kṛṣṇa who is known as Govinda is the Supreme Godhead. He has an eternal blissful spiritual body. He is the origin of all. He has no other origin and He is the prime cause of all causes.[Bs. 5.1]
To realize Parmatmā or Bhagavān, the process is given by Bhagavān Himself.
To know Him, we have to take the instruction given by Bhagavān Himself. We cannot manufacture ideas to know Bhagavān. We cannot speculate on Bhagavān.
The Vedas inform us:
Nayam atma pravacanena labhyah: If one is very good speaker, it is not that he can understand Bhagavan.
Nayam atma pravacanena labhyo na medhaya: If one is very meritorious, great scientist, philosopher, it does not mean that he can understand Bhagavān.
Nayam atma pravacanena labhyo na bahuna srutena: If one is very highly educated, highly learned in Vedic knowledge, he also cannot understand Bhagavān.
Bhagavān can be understood by the mercy of Bhagavān. That is the process. Therefore Bhagavan is mercifully explaining Himself. We have to take advantage of it. Then we can understand Bhagavān.
athapi te deva padambuja-dvaya-
prasada-lesanugrhita eva hi
janati tattvam bhagavan-mahimno
na canya eko 'pi ciram vicinvan
"My Lord, one who has got a little mercy of Yourself, he can understand. Others, who has not received Your mercy, he may speculate for millions of years, still he cannot understand."
These are the verdicts of the Vedas. So we can understand Bhagavan by the mercy of Bhagavān. Not by speculation, not by learning, not by speaking etc.
In other words, if we want to see the sun at night, can millions of torches/lights help us see the sun? No. Sun can only be seen by it's own mercy - sun-light. Similarly, Lord can only be known through His own mercy.
The process is given by Lord Himself:
śrī-bhagavān uvāca
mayy āsakta-manāḥ pārtha
yogaḿ yuñjan mad-āśrayaḥ
asaḿśayaḿ samagraḿ māḿ
yathā jñāsyasi tac chṛṇu
The Supreme Personality of Godhead said: Now hear, O son of Pṛthā, how by practicing yoga in full consciousness of Me, with mind attached to Me, you can know Me in full, free from doubt. [B.G. 7.1]
patram pushpam phalam toyam
yo me bhaktya prayacchati
tad aham bhakty-upahritam
asnami prayatatmanah
If one offers Me with love and devotion a leaf, a flower, fruit or water, I will accept it. [B.G. 9.26]
This is real yoga, how to become attached to the service of the Lord.
yoginam api sarvesam
mad-gatenantar-atmana
sraddhavan bhajate yo mam
sa me yuktatamo matah
And of all yogis, the one with great faith who always abides in Me, thinks of Me within himself, and renders transcendental loving service to Me -- he is the most intimately united with Me in yoga and is the highest of all. That is My opinion. [B.G. 6.47]