Q] Can a bAlA upAsaka worship shrIchakra?
Anyone can do anything. The question really is what is right according to shAstra dR^iShti. Though shrIchakra represents a sarva-samaShti shakti chakra, bAlA is one of the a~Nga shaktis of lalitA in spite of the abheda that exists between bAlA, bhairavI and sundarI. It is said, bAlalIlA vishiShTatvAdbAleti, lalitA on account of her bAlAlIlA visheSha, is called bAlA. But apart from mantra and svarUpa, difference can also be seen between lalitA and bAlA in terms of adhiShThAna, which is very important in terms of shAkta saguNopAsanA. The adhiShThAna of bAla is in svAdhishThAna chakra, which is the seat of letters from baM to laM, evident in her very name.
Moreover, a specific yantra for bAlA is described in various tantras and this needs to be worshipped by upAsakas of bAlA parameshvarI.
Acharya gauDapAda describes the yantra thus:
tadeva patravasudvayayuktamanusvaraM kumArIsadanam |
sha~NkarAraNya describes the resulting bAlA chakra thus: bindu trikoNa ShaTkoNa vR^ittAntaraShTadalapadma vR^ittabahiraShTadalapadma chaturashrAtmakaM bAlA chakraM bhavati |
An alternate saptAvaraNa yantra is described in traipura siddhAnta:
tato yantraM likheddhImAn bindumAdau likehnnaraH |
trikoNaM vilikhet pashchAt ShaTkoNaM vilikhettataH ||
dalAShTakaM liketpashchAt tadbahirvR^ittamAlikhet |
chaturashraM likhet pashchAt chaturdvArasamanvitam ||
maNDalaM vilikeht pashchAdyantrametadudIritam |
saptamAvaraNopetAM shrIbAlAM praNamAmyaham ||
As the upAsanA of bAlA through this yantra is taught as a preparatory practice to the worship of lalitA in shrIchakra by various upAsana shastras, the yuktatva of worship of bAlA in her own yantra becomes evident. This is the case when the mukhya devatA worshipped is bAlA and not as a parivAra devatA of shrI lalitA. As there is an explicit pramANa in this regard, I do not see the need to resort to mImAmsA to support this statement. To summarize, there can be two cases:
a. The person is an upAsaka of bAlA alone: In this case it is quite evident that he needs to worship bAlA yantra. The same shAstras which describe shrIyantra in relation to lalitA, speak of a separate bAlA yantra. If the upAsaka of bAlA could worship shrIyantra, bAlA yantra would more or less be redundant. trikUTA rahasya states pa~nchadashI as the least requirement for pravesha into the navAvaraNa yantra of sundarI. bAlA (tryakSharI or shadakSharI) is a pUrvA~Nga of lalitA like mahAgaNapati, worshipped prior to undertaking the upAsanA of lalitA.
b. The person is an upAsaka of sundarI: If this is the case, in both nitya and naimittika pakShas, he would need to worship sundarI and not bAlA. This is based on the assumption that he received initiation into the Supreme vidyA of sundarI after the prescribed upAsanA of bAlA, generally a pre-requisite in many sampradayas. The lack of need for worshipping pUrvAnga devatas after initiation into the mukhya vidyA is discussed at length twice by rAmeshvara sUrin. In the case of kAmya pakSha, if one desires to worship bAlA for a specific purpose, he can then make use of the sarva-shakti-samaShTitva clause of the shrIchakra and worship bAlA within the shrIchakra, based on the pramANa from tantrarAja or kAdimata.