The academy conversion process, set out by the DfE here states that governing bodies must consult parents on the decision to convert, but only once they have taken the decision.
The big question is whether it will be a stand-alone, or converter academy, or whether it will join in with a chain or cluster of academies, or be a sponsored academies. In the last two cases, you need to be aware that the sponsor, or chain, takes a top-slice of the school's budget to pay for services that would otherwise be provided by the local authority. When we were going through this process I did quite a bit of digging on this, and the top-slice is normally between 2-7% of the school's budget (with larger rather than smaller being the norm), and in our case, the amount that the LA retained is 1.1% of total budget allocation. Plus if the school is in good financial health the grant that can be made available to cover the considerable costs of conversion is normally not available. So, financially, there are no advantages to conversion.
There is also a loss of accountability. Schools are no longer democratically accountable through locally-elected councillors, and the governing bodies of academies, though they have to have 2 parents, do not have to have any other local people on academies are governed by a board of trustees, which takes all the financial and strategic decisions, and the school has board of governors which is responsible to the trustees. And the whole thing reports directly to the Secretary of State for schools so if an academy is failing they can't, for example, get help from the local authority; and if a sponsor isn't providing the support they should do, or a chain is moving all the best teachers from your school to other academies in the chain (as they are entitled to do because teachers are employed by the chain rather than the school) you have no recourse to an independent authority -- except the Secretary of State.