Mr Silverstone took over last year following a damaging dispute between the previous administration and Rabbi Binyamin Bar, who was sacked and then reinstated after members made clear their support for him.
"Things have started to move for the first time in decades," said Mr Silverstone, 66, who has lived in the area for 45 years. "I can leave this job happy. I can say with a lot of confidence that Southend has a long future in front of it.
"We are not going to die away. After 20, 30, even 40 years of decline, this is our revitalisation.
"They [the Charedim] are the catalyst to bring a new generation of children, shops and infrastructure to Southend and Westcliff."
Five Charedim - two of whom have recently joined the shul - were at the meeting, which Mr Silverstone said had "brought the community together.
"Three or four families had preconceived ideas about what would happen to our community and lots of other people were receiving gossip, innuendo and downright disinformation, which needed to be put right."
The great majority of those at the meeting supported Charedim joining the congregation.
In a statement afterwards, Charedi representative Shlomo Fink said: "We have been very warmly welcomed. We are very excited about the future and look forward to offering our help to the community in any way we can."
Going forward, Mr Silverstone said divisions in the community caused by the dispute over the rabbi had healed.
Rabbi Bar agreed, saying: "Some choose to be a bit bitter about it but as a whole we are unified and work together."
As an indicator of the shul's current state, it has hosted six weddings and the same number of barmitzvahs this year. And with a mikveh that the shul council claims as "the best in Europe", an on-site kosher shop ripe for expansion, direct rail links into central London and the attraction of the "therapeutic" seaside, Mr Silverstone is preparing for an increase in membership.
"We are one of the very few shuls outside London who have morning and evening services seven days a week," he pointed out. SWHC's £520 yearly membership fee for a couple (including burial contributions) compares favourably to London congregations.
For Charedim, a major selling point was cheaper housing than Stamford Hill and Rabbi Bar talked of plans for an eruv as well as the potential for the shul cheder to double as a Charedi school.
Mr Silverstone said collaboration made sense.
"If we don't help each other, we'll die. So we help each other. There's no us and them."
Rabbi Bar stressed the willingness of the new arrivals to work with the existing congregation. "They will eventually have their own shul but we're going to have many areas we will work in partnership, like the shop and an eruv.
"They want to belong and we're delighted with that. They are very tolerant and non-judgemental and I'm sure they'll be an asset to the community."
At Jewish Care's centre, manager Hilary De Martino said it was "the hub of the community".
The charity sold its Raymond House care home in 2012 but offers independent living with round-the-clock support through Shebson Lodge, sited above the community centre.
All but four of the 16 flats have a sea view and Ms De Martino reported that one client in his 80s had learned to surf over the past few months.
"It's not just about the building. We are actively engaging 200 people per week inside and outside the centre."
Strengthened links with local Jewry had resulted in increased support for events such as the monthly salt beef supper. "A big aim" was involving those aged 55 to 75 who come to the town to retire.
The charity also provides home care, a kosher-style café at the centre and hot meals on wheels. It would like to organise educational tours for local schools taking in the town's Jewish life.
Dementia patients can enjoy gardening in the centre's plot, where sunflowers and potatoes line its soil.
"Their memories may be going but their self esteem isn't," Ms De Martino said.
