Cynog Dafis, a policy director for the party, says more pay for the profession is vital if FE staff are to be given the flexibility to work in school sixth forms.
Funding of Wales' sixth-form and general FE colleges was taken over by Education and Learning Wales when it was launched in parallel with the Learning and Skills Council in England, in April this year.
"We really need to improve pay and conditions so they match school sixth-forms - and so that FE college staff can work in schools and vice versa," he said.
"While there has been some increase in accountability of colleges through the setting up of ELWA under the Learning and Skills Act, as a long-term objective, we were opposed to incorporation of colleges when it happened and that remains our position. But there are other problems which need to be addressed first."
He says that while the Welsh Assembly does not have tax-raising powers, the country needs a fairer dealfrom the Treasury, requiring an extra pound;600 million to catch up with the increased education spending in England.
It says the country also gets short-changed when it receives European structural funds because the grant results in reduced funds from the UK treasury.
Effectively, he argues, this means England indirectly gets a slice of the funding which was intended for Wales.
These anomalies, he says, contribute to the case for Wales to have its own supplementary tax-raising powers in addition to its funding from Whitehall. This is the case for the Scottish parliament, although this power has not yet been taken up north of the border.
Plaid Cymru's frustration about the comparison between English and Welsh education is summarised in its manifesto, which says: "Many decisions on education have, of course, been devolved to the Assembly but Westminster's influence is heavy in terms of policy framework and the resources available.
"This is particularly relevant now that expenditure per head on education in Wales will be lower than in England over the coming years."