God told Moses to begin synagogues when they met on the mountain during the Exodus
Synagogues were created during the Babylonian captivity, according to Psalm 134
There is no mention of synagogues in the OT, so we don't know when or how or when they began
The point is, God started the synagogue by special revelation, and that's why Jesus participated in the synagogue regularly
If it is expedient, and it is part of the culture and is not wrong, there is no reason to refuse to participate. This can be applied to the use of instruments, the innovation of Sunday School classes or small groups, etc.
If God Himself submitted to daily routine of Scripture reading and memorized prayers, we need not consider such spiritual disciplines to be beneath us.
Jesus was not spiritual enough to realize He didn't have to be in a synagogue regularly.
Maybe church attendance as the assembly is at least as much for the sake of others as it is for ourselves being fed.
Less formal than the Temple, with comparative equality among all members
More formal than most evangelical churches, with cyclical readings and memorized prayers
Relatively large small groups (of 40-100), formed by neighborhood or affinity
The sermon/message was delivered sitting down, and tended to be less formal and prepared than modern sermons are
All members stood most of the time, for the singing, reading and praying
They always had special music, usually sung by a teenage girl accompanied by a woman named Betty on the piano
The seating is communal, somewhat in the round
Women and children were separated from the men, so that the prayers of the men would not be distracted
The orientation was toward Jerusalem, when possible
There is a significant ark that stores the Torah
There is usually a bimah, or raised platform, suitable for reading and other acts of leadership
Standing behind a pulpit as a sign of authority
Sitting on a stool as a sign of informal sharing
Sitting on a chair as a sign of authority
Standing with hands raised as a sign of submission
Stand facing Jerusalem with arms raised and eyes open
Sitting neutrally in a pew with eyes closed and head bowed
Kneeling and bowing five times to the east
Eyes closed, hands raised, tears streaming down face
Call to worship, hymns, special music, offering, sermon, invitation, closing chorus
Opening blessing, recited prayers, set reading, flexible reading, message, closing blessing
Invocation, Kyrie, Gloria, readings, Credo, Table, Benediction
Informal structure with no particular order