I would generally advise against using terms such as "forward thinking." For one, ascribing values to an entire religious minority is bound to produce inaccuracies. Not all Quakers were abolitionist. Second, most Quaker abolitionists would not have considered themselves "forward thinking." To most Quakers (and any Christian involved in the abolition debate for that matter), they were acting in accordance with their religious beliefs. That's a very different thing than forward thinking. I've had the luxury of reading transcripts from abolition debates on the religious implications of slavery, and neither side seemed particularly concerned with whether or not they were "forward thinking." To them, the issue of slavery was one with deep hermeneutical implications on what Christian morality meant. Using terms like forward thinking runs the risk of dismissing the beliefs, however abhorrent to our modern eyes, of Christians who most certainly believed what they were saying. History is a vastly more complicated process than most books let on, and categorizing groups as "forward thinking" or "backwards" does more damage than good to understanding historical processes.

To answer your question: yes, most Quakers espoused political beliefs that a modern audience would find agreeable (i.e. "forward thinking"), but with qualifications. The majority of Quakers were certainly pro-abolition by the late 18th century, but this does not mean that Quakers were always abolitionist. The Philadelphia Yearly Meeting condemned slavery in 1696, but slavery remained legal for some time after that. Remember that in the early 1700s, slaves constituted as much as 10 percent of the population of Philadelphia. As such, slavery was part of the economic system of Philadelphia in its early years despite having a large population of Quakers. The life of Benjamin Lay (born 1682) is a good representation of the development of Quaker abolitionism. Although he was an outspoken abolitionist in the embryonic days of Quaker abolition, the Overseers of the Press (who acted with the authority of the Philadelphia Yearly Meeting) opposed him and sought to use their control of the press to clamp down on his abolitionist rhetoric.

And not all Quakers were abolitionist. George Fox White, a Pennsylvania pastor and member of the Hicksite branch of Quakerism, responded to the deepening political divide of the 1830s by asking Quakers to forgo political partisanship in the abolition debate. While not necessarily pro-slavery, George Fox White was hardly what could be called an abolitionist.

It's tempting to assume that the egalitarian nature of Quakerism would make them unquestionably abolitionist and that Quakers are inherently more forward thinking, but history presents a more complicated picture. As for the question of whether or not Quakers were more forward thinking than their contemporaries, I think this a dangerous way to approach the matter. Christians who partook in the debate had genuine religious convictions backing their arguments. Here's an argument made by the proslavery reverend NL Blanchard: Who denies (what that text imports) that in the privileges of the Christian church and in the blessed hopes of the gospel, there are no distinctions- that at the table of the Lord the richest man takes his seat by the poorest of the poor? But a king is a king still, though his meanest subject is on par with himself in all things of religion. The equality of all men on the great platform of Christian privileges and hope, does not prevent great inequalities in their civil condition…The equality of a Jew and his slave in their right to the Passover, did in no wise destroy their relation to each other as master and slave. Trying to understand Christian interpretation can (and perhaps should) be disconcerting to a modern audience, but dismissing their arguments as "backwards thinking" or elevating the position of Quakers as "forwards thinking" can lead to a narrow understanding of history.

If you're interested in reading more about how Christian hermeneutics evolved for both abolitionists and anti-abolitionists, I cannot recommend the work of J. Albert Harril enough. His article "The Use of the New Testament in the American Slave Controversy: A Case History in the Hermeneutical Tension between Biblical Criticism and Christian Moral Debate" is a fantastic resource.

Sources:

Brycchan Carey From Peace to Freedom: Quaker Rhetoric and the Birth of American Slavery, 1657-176.

Blanchard and N.L. Rice, A Debate on Slavery Held in the City of Cincinnati, on the First, Second, Third, and Sixth Days of October, 1845, Upon the Question: Is Slave-Holding in Itself Sinful, and the Relation Between Master and Slave, a Sinful Relation?